nacos is coming

.gitignore

@@ -0,0 +1,10 @@
+# Except this file !.gitignore 
+.classpath
+.project
+.settings
+target
+.project
+.idea
+.DS_Store
+/logs
+*.iml

.travis.yml

@@ -0,0 +1,31 @@
+notifications:
+  email:
+    recipients:
+      - nacos_dev@linux.alibaba.com
+      - dev-nacos@googlegroups.com
+  on_success: change
+  on_failure: always
+
+language: java
+
+matrix:
+  include:
+  # On OSX, run with default JDK only.
+  # - os: osx
+  # On Linux, run with specific JDKs only.
+  - os: linux
+    env: CUSTOM_JDK="oraclejdk8"
+
+before_install:
+  - echo 'MAVEN_OPTS="$MAVEN_OPTS -Xmx1024m -XX:MaxPermSize=512m -XX:+BytecodeVerificationLocal"' >> ~/.mavenrc
+  - cat ~/.mavenrc
+  - if [ "$TRAVIS_OS_NAME" == "osx" ]; then export JAVA_HOME=$(/usr/libexec/java_home); fi
+  - if [ "$TRAVIS_OS_NAME" == "linux" ]; then jdk_switcher use "$CUSTOM_JDK"; fi
+
+script:
+  - travis_retry mvn -B clean apache-rat:check
+  - travis_retry mvn -B package jacoco:report coveralls:report
+
+after_success:
+  - mvn clean install -Pit-test
+  - mvn sonar:sonar -Psonar-apache

BUILDING

@@ -0,0 +1,38 @@
+Build Instructions for NACOS
+
+====================================================
+
+(1) Prerequisites
+
+    JDK 1.8+ is required in order to compile and run Nacos.
+
+    nacos utilizes Maven as a distribution management and packaging tool. Version 3.0.3 or later is required.
+    Maven installation and configuration instructions can be found here:
+
+    http://maven.apache.org/run-maven/index.html
+
+
+(2) Run test cases
+
+    Execute the following command in order to compile and run test cases of each components:
+
+    $ mvn test
+
+
+(3) Import projects to Eclipse IDE
+
+    First, generate eclipse project files:
+
+    $ mvn -U eclipse:eclipse
+
+    Then, import to eclipse by specifying the root directory of the project via:
+
+    [File] > [Import] > [Existing Projects into Workspace].
+
+
+(4) Build distribution packages
+
+    Execute the following command in order to build the tar.gz packages and install JAR into local repository:
+
+	#build nacos
+    $ mvn -Prelease-nacos -DskipTests clean install -U

CONTRIBUTING.md

@@ -0,0 +1,31 @@
+## How To Contribute
+
+We are always very happy to have contributions, whether for trivial cleanups or big new features.
+We want to have high quality, well documented codes for each programming language.
+
+Nor is code the only way to contribute to the project. We strongly value documentation, integration with other project, and gladly accept improvements for these aspects.
+
+## Contributing code
+
+To submit a change for inclusion, please do the following:
+
+#### If the change is non-trivial please include some unit tests that cover the new functionality.
+#### If you are introducing a completely new feature or API it is a good idea to start a wiki and get consensus on the basic design first.
+#### It is our job to follow up on patches in a timely fashion. Nag us if we aren't doing our job (sometimes we drop things).
+
+## Becoming a Committer
+
+We are always interested in adding new contributors. What we look for are series of contributions, good taste and ongoing interest in the project. If you are interested in becoming a committer, please let one of the existing committers know and they can help you walk through the process.
+
+Nowadays,we have several important contribution points:
+#### Wiki & JavaDoc
+#### Nacos Console
+#### Nacos SDK(C++\.Net\Php\Python\Go\Node.js)
+
+##### Prerequisite
+If you want to contribute the above listing points, you must abide our some prerequisites:
+
+###### Readability - API must have Javadoc,some very important methods also must have javadoc
+###### Testability - 80% above unit test coverage about main process
+###### Maintainability - Comply with our [PMD spec](style/codeStyle.xml), and at least 3 month update frequency
+###### Deployability - We encourage you to deploy into [maven repository](http://search.maven.org/)

LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (properties) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

NOTICE

@@ -0,0 +1,32 @@
+Nacos
+Copyright 2018-2019 The Apache Software Foundation
+
+This product includes software developed at
+The Alibaba MiddleWare Group.
+
+------
+This product has a bundle Spring Boot:
+                            The Spring Boot Project
+                            =================
+
+Please visit the Spring Boot web site for more information:
+
+  * https://spring.io/projects/spring-boot
+
+Copyright 2014 The Spring Boot Project
+
+The Spring Boot Project licenses this file to you under the Apache License,
+version 2.0 (the "License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at:
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+License for the specific language governing permissions and limitations
+under the License.
+
+Also, please refer to each LICENSE.<component>.txt file, which is located in
+the 'license' directory of the distribution file, for the license terms of the
+components that this product depends on.

README.md

@@ -0,0 +1,49 @@
+## Nacos 
+
+
+[![Gitter](https://badges.gitter.im/alibaba/nacos.svg)](https://gitter.im/alibaba/nacos?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)   [![License](https://img.shields.io/badge/license-Apache%202-4EB1BA.svg)](https://www.apache.org/licenses/LICENSE-2.0.html)
+[![Gitter](https://travis-ci.org/alibaba/nacos.svg?branch=master)](https://travis-ci.org/alibaba/nacos)
+
+-------
+<img src="doc/Nacos_Logo.png" width="50%" height="50%" />
+Nacos is an easy-to-use platform desgined for dynamic service discovery and configuration and service management. It helps you to build cloud native applications and microservices platform easily.
+
+Service is a first-class citizen in Nacos. Nacos supports almost all type of services，for example，[Dubbo/gRPC service](xx)、[Spring Cloud RESTFul service](xx) or [Kubernetes service](xx).
+
+Nacos provides four major funcations.
+
+* **Service Discovery and Service Health Check** 
+    
+    Nacos makes it simple for services to register themselves and to discover other services via a DNS or HTTP interface. Nacos also provides real-time healthchecks of services to prevent sending requests to unhealthy hosts or service instance.
+
+* **Dynamic Configuration Management**
+  
+  Dynamic Configuration Service allows you to manage configurations of all services in a centralized and dynamic manner across all environments. Nacos eliminates the need to redeploy applications and services when configurations are updated，which makes configuration changes more efficient and agile.
+
+* **Dynamic DNS Service**
+
+   Nacos supports weighted routing, making it easier for you to implement mid-tier load balancing, flexible routing policies, flow control, and simple DNS resolution services in the production environment within your data center. It helps you to implement DNS-based service discovery easily and prevent applications from coupling to vendor-specific service discovery APIs.
+
+* **Service and MetaData Management**
+	
+	Nacos provides an easy-to-use service dashboard to help you manage your services metadata, configuration, kubernetes DNS, service health and metrics statistics.
+ 
+
+## Quick Start (TODO)
+It is super easy to get started with your first project.
+
+https://nacos.io/#/docs/quick-start.md
+
+Quick start for other open-source projects:
+
+[quick start with spring cloud](xx)
+[quick start with dubbo](xx)
+[quick start with kubernetes](xx)
+[more...](xx)
+
+
+## Documentation
+
+You can view full documentation on the Nacos website:
+
+[https://nacos.io/#/blog](https://nacos.io/#/blog)

client/pom.xml

@@ -0,0 +1,107 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<parent>
+		<groupId>com.alibaba.nacos</groupId>
+		<artifactId>nacos-all</artifactId>
+		<version>0.1.0</version>
+	</parent>
+
+	<modelVersion>4.0.0</modelVersion>
+
+	<artifactId>nacos-client</artifactId>
+	<packaging>jar</packaging>
+
+	<name>nacos-client ${project.version}</name>
+	<url>http://maven.apache.org</url>
+
+	<properties>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+	</properties>
+
+	<dependencies>
+	    <dependency>
+			<groupId>org.slf4j</groupId>
+			<artifactId>slf4j-api</artifactId>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>log4j</groupId>
+			<artifactId>log4j</artifactId>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.logging.log4j</groupId>
+			<artifactId>log4j-core</artifactId>
+			<version>2.8.2</version>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>commons-logging</groupId>
+			<artifactId>commons-logging</artifactId>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.slf4j</groupId>
+			<artifactId>slf4j-log4j12</artifactId>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.logging.log4j</groupId>
+			<artifactId>log4j-slf4j-impl</artifactId>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.slf4j</groupId>
+			<artifactId>jcl-over-slf4j</artifactId>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>junit</groupId>
+			<artifactId>junit</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>${project.groupId}</groupId>
+			<artifactId>nacos-common</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>com.alibaba</groupId>
+			<artifactId>fastjson</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>ch.qos.logback</groupId>
+			<artifactId>logback-classic</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>ch.qos.logback</groupId>
+			<artifactId>logback-core</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>com.google.guava</groupId>
+			<artifactId>guava</artifactId>
+		</dependency>
+
+		<dependency>
+			<artifactId>commons-codec</artifactId>
+			<groupId>commons-codec</groupId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.codehaus.jackson</groupId>
+			<artifactId>jackson-mapper-lgpl</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>net.jcip</groupId>
+			<artifactId>jcip-annotations</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>com.github.spotbugs</groupId>
+			<artifactId>spotbugs-annotations</artifactId>
+			<optional>true</optional>
+		</dependency>
+	</dependencies>
+
+</project>

client/src/main/java/com/alibaba/nacos/api/NacosFactory.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api;
+
+import java.util.Properties;
+
+import com.alibaba.nacos.api.config.ConfigFactory;
+import com.alibaba.nacos.api.config.ConfigService;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.api.naming.NamingFactory;
+import com.alibaba.nacos.api.naming.NamingService;
+
+/**
+ * Nacos Factory
+ * 
+ * @author Nacos
+ *
+ */
+public class NacosFactory {
+
+	/**
+	 * Create config
+	 * 
+	 * @param properties
+	 *            init param
+	 * @return config
+	 * @throws NacosException
+	 *             Exception
+	 */
+	public static ConfigService createConfigService(Properties properties) throws NacosException {
+		return ConfigFactory.createConfigService(properties);
+	}
+
+	/**
+	 * Create config
+	 * 
+	 * @param serverAddr
+	 *            server list
+	 * @return config
+	 * @throws NacosException
+	 *             Exception
+	 */
+	public static ConfigService createConfigService(String serverAddr) throws NacosException {
+		return ConfigFactory.createConfigService(serverAddr);
+	}
+
+	/**
+	 * Create Naming
+	 * 
+	 * @param serverAddr
+	 *            server list
+	 * @return Naming
+	 * @throws NacosException
+	 *             Exception
+	 */
+	public static NamingService createNamingService(String serverAddr) throws NacosException {
+		return NamingFactory.createNamingService(serverAddr);
+	}
+
+	/**
+	 * Create Naming
+	 * 
+	 * @param properties
+	 *            init param
+	 * @return Naming
+	 * @throws NacosException
+	 *             Exception
+	 */
+	public static NamingService createNamingService(Properties properties) throws NacosException {
+		return NamingFactory.createNamingService(properties);
+	}
+
+}

client/src/main/java/com/alibaba/nacos/api/PropertyKeyConst.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api;
+
+/**
+ * properties key
+ * @author Nacos
+ *
+ */
+public class PropertyKeyConst {
+
+	public final static String ENDPOINT = "endpoint";
+	public final static String NAMESPACE = "namespace";
+	public final static String ACCESS_KEY = "accessKey";
+	public final static String SECRET_KEY = "secretKey";
+	public final static String SERVER_ADDR = "serverAddr";
+	public final static String CONTEXT_PATH = "contextPath";
+	public final static String CLUSTER_NAME = "clusterName";
+	public final static String ENCODE = "encode";
+	
+}

client/src/main/java/com/alibaba/nacos/api/config/ConfigFactory.java

@@ -0,0 +1,60 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config;
+
+import java.util.Properties;
+
+import com.alibaba.nacos.api.PropertyKeyConst;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.client.config.NacosConfigService;
+
+/**
+ * Config Factory
+ * 
+ * @author Nacos
+ *
+ */
+public class ConfigFactory {
+
+	/**
+	 * Create Config
+	 * 
+	 * @param properties
+	 *            init param
+	 * @return Config
+	 * @throws NacosException
+	 *             Exception
+	 */
+	public static ConfigService createConfigService(Properties properties) throws NacosException {
+		return new NacosConfigService(properties);
+	}
+
+	/**
+	 * Create Config
+	 * 
+	 * @param ServerAddr
+	 *            serverlist
+	 * @return Config
+	 * @throws NacosException
+	 *             Exception
+	 */
+	public static ConfigService createConfigService(String serverAddr) throws NacosException {
+		Properties properties = new Properties();
+		properties.put(PropertyKeyConst.SERVER_ADDR, serverAddr);
+		return new NacosConfigService(properties);
+	}
+
+}

client/src/main/java/com/alibaba/nacos/api/config/ConfigService.java

@@ -0,0 +1,103 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config;
+
+import com.alibaba.nacos.api.config.listener.Listener;
+import com.alibaba.nacos.api.exception.NacosException;
+
+/**
+ * Config Interface
+ * 
+ * @author Nacos
+ *
+ */
+public interface ConfigService {
+
+	/**
+	 * Get Configuration
+	 * 
+	 * @param dataId
+	 *            Config ID
+	 * @param group
+	 *            Config Group
+	 * @param timeoutMs
+	 *            read timeout
+	 * @return config value
+	 * @throws NacosException
+	 *             NacosException
+	 */
+	public String getConfig(String dataId, String group, long timeoutMs) throws NacosException;
+
+	/**
+	 * Add a listener to the configuration, after the server to modify the
+	 * configuration, the client will use the incoming listener callback.
+	 * Recommended asynchronous processing, the application can implement the
+	 * getExecutor method in the ManagerListener, provide a thread pool of
+	 * execution. If provided, use the main thread callback, May block other
+	 * configurations or be blocked by other configurations.
+	 * 
+	 * @param dataId
+	 *            Config ID
+	 * @param group
+	 *            Config Group
+	 * @param listener
+	 *            listener
+	 * @throws NacosException
+	 *             NacosException
+	 */
+	public void addListener(String dataId, String group, Listener listener) throws NacosException;
+
+	/**
+	 * publish config.
+	 * 
+	 * @param dataId
+	 *            Config ID
+	 * @param group
+	 *            Config Group
+	 * @param content
+	 *            Config Content
+	 * @return Whether publish
+	 * @throws NacosException
+	 *             NacosException
+	 */
+	public boolean publishConfig(String dataId, String group, String content) throws NacosException;
+
+	/**
+	 * Remove Config
+	 * 
+	 * @param dataId
+	 *            Config ID
+	 * @param group
+	 *            Config Group
+	 * @return whether remove
+	 * @throws NacosException
+	 *             NacosException
+	 */
+	public boolean removeConfig(String dataId, String group) throws NacosException;
+
+	/**
+	 * Remove Listener
+	 * 
+	 * @param dataId
+	 *            Config ID
+	 * @param group
+	 *            Config Group
+	 * @param listener
+	 *            listener
+	 */
+	public void removeListener(String dataId, String group, Listener listener);
+
+}

client/src/main/java/com/alibaba/nacos/api/config/filter/IConfigContext.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config.filter;
+
+/**
+ * Config Context Interface
+ * 
+ * @author Nacos
+ *
+ */
+public interface IConfigContext {
+	/**
+	 * get context by key
+	 * 
+	 * @param key
+	 * @return context
+	 */
+	public Object getParameter(String key);
+
+	/**
+	 * set context
+	 * 
+	 * @param key
+	 *            key
+	 * @param value
+	 *            value
+	 */
+	public void setParameter(String key, Object value);
+}

client/src/main/java/com/alibaba/nacos/api/config/filter/IConfigFilter.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config.filter;
+
+import com.alibaba.nacos.api.exception.NacosException;
+
+/**
+ * Config Filter Interface
+ * 
+ * @author Nacos
+ *
+ */
+public interface IConfigFilter {
+	/**
+	 * Init Fuction
+	 * 
+	 * @param filterConfig
+	 *            Filter Config
+	 */
+	void init(IFilterConfig filterConfig);
+
+	/**
+	 * do filter
+	 * 
+	 * @param request
+	 *            request
+	 * @param response
+	 *            response
+	 * @param filterChain
+	 *            filter Chain
+	 * @throws NacosException
+	 *             exception
+	 */
+	void doFilter(IConfigRequest request, IConfigResponse response, IConfigFilterChain filterChain)
+			throws NacosException;
+
+	/**
+	 * deploy
+	 */
+	void deploy();
+
+	/**
+	 * order
+	 * 
+	 * @return
+	 */
+	int getOrder();
+
+	/**
+	 * filterName
+	 * 
+	 * @return
+	 */
+	String getFilterName();
+
+}

client/src/main/java/com/alibaba/nacos/api/config/filter/IConfigFilterChain.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config.filter;
+
+import com.alibaba.nacos.api.exception.NacosException;
+
+/**
+ * Config Filter Chain Interface
+ * 
+ * @author Nacos
+ *
+ */
+public interface IConfigFilterChain {
+	/**
+	 * Filter aciton
+	 * 
+	 * @param request
+	 *            request
+	 * @param response
+	 *            response
+	 * @throws NacosException
+	 *             NacosException
+	 */
+	public void doFilter(IConfigRequest request, IConfigResponse response) throws NacosException;
+	
+}

client/src/main/java/com/alibaba/nacos/api/config/filter/IConfigRequest.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config.filter;
+
+/**
+ * Config Request Interface
+ * 
+ * @author Nacos
+ *
+ */
+public interface IConfigRequest {
+	/**
+	 * get param
+	 * 
+	 * @param key
+	 *            key
+	 * @return value
+	 */
+	public Object getParameter(String key);
+
+	/**
+	 * get config context
+	 * 
+	 * @return
+	 */
+	public IConfigContext getConfigContext();
+
+}

client/src/main/java/com/alibaba/nacos/api/config/filter/IConfigResponse.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config.filter;
+
+/**
+ * Config Response Interface
+ * 
+ * @author Nacos
+ *
+ */
+public interface IConfigResponse {
+	/**
+	 * get param
+	 * 
+	 * @param key
+	 *            key
+	 * @return value
+	 */
+	public Object getParameter(String key);
+
+	/**
+	 * get context
+	 * 
+	 * @return configContext
+	 */
+	public IConfigContext getConfigContext();
+
+}

client/src/main/java/com/alibaba/nacos/api/config/filter/IFilterConfig.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config.filter;
+/**
+ * Filter Config Interface
+ * @author Nacos
+ *
+ */
+public interface IFilterConfig {
+
+	/**
+	 * get filter name
+	 * 
+	 * @return
+	 */
+	public String getFilterName();
+
+	/**
+	 * get param
+	 * 
+	 * @param name
+	 * @return param
+	 */
+	public Object getInitParameter(String name);
+
+}

client/src/main/java/com/alibaba/nacos/api/config/listener/AbstractListener.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config.listener;
+
+import java.util.concurrent.Executor;
+
+/**
+ * Listner Adapter,use default notify thread
+ * 
+ * @author water.lyl
+ *
+ */
+@SuppressWarnings("PMD.AbstractClassShouldStartWithAbstractNamingRule")
+public abstract class AbstractListener implements Listener {
+
+	/**
+	 * use default Executor
+	 */
+    public Executor getExecutor() {
+        return null;
+    }
+
+}

client/src/main/java/com/alibaba/nacos/api/config/listener/AbstractSharedListener.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config.listener;
+
+import java.util.concurrent.Executor;
+
+/**
+ * shared listener
+ * 
+ * @author Nacos
+ *
+ */
+@SuppressWarnings("PMD.AbstractClassShouldStartWithAbstractNamingRule")
+public abstract class AbstractSharedListener implements Listener {
+    private volatile String dataId;
+    private volatile String group;
+
+    final public void fillContext(String dataId, String group) {
+        this.dataId = dataId;
+        this.group = group;
+    }
+
+    @Override
+    final public void receiveConfigInfo(String configInfo) {
+        innerReceive(dataId, group, configInfo);
+    }
+
+    @Override
+    public Executor getExecutor() {
+        return null;
+    }
+
+	/**
+	 * receive
+	 * 
+	 * @param dataId
+	 *            data ID
+	 * @param group
+	 *            group
+	 * @param configInfo
+	 *            content
+	 */
+    public abstract void innerReceive(String dataId, String group, String configInfo);
+}

client/src/main/java/com/alibaba/nacos/api/config/listener/Listener.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.config.listener;
+
+import java.util.concurrent.Executor;
+
+
+/**
+ * Listener for watch config
+ * 
+ * @author Nacos
+ * 
+ */
+public interface Listener {
+
+	/**
+	 * Executor to excute this receive
+	 * 
+	 * @return Executor
+	 */
+    public Executor getExecutor();
+
+
+    /**
+     * 接收配置信息
+     * 
+     * @param configInfo 配置值
+     */
+    public void receiveConfigInfo(final String configInfo);
+}

client/src/main/java/com/alibaba/nacos/api/exception/NacosException.java

@@ -0,0 +1,110 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.exception;
+
+/**
+ * Nacos Exception
+ * 
+ * @author Nacos
+ *
+ */
+public class NacosException extends Exception{
+
+	/**
+	 * serialVersionUID
+	 */
+	private static final long serialVersionUID = -3913902031489277776L;
+
+	private int errCode;
+
+	private String errMsg;
+	
+	public NacosException() {
+	};
+
+	public NacosException(int errCode, String errMsg) {
+		this.errCode = errCode;
+		this.errMsg = errMsg;
+	}
+	
+	public int getErrCode() {
+		return errCode;
+	}
+
+	public String getErrMsg() {
+		return errMsg;
+	}
+
+	public void setErrCode(int errCode) {
+		this.errCode = errCode;
+	}
+
+	public void setErrMsg(String errMsg) {
+		this.errMsg = errMsg;
+	}
+	
+	@Override
+	public String toString() {
+		return "ErrCode:" + errCode + ",ErrMsg:" + errMsg;
+	}
+
+	/**
+	 * client error code 
+	 * -400 -503 throw exception to user
+	 */
+	/**
+	 *  invalid param（参数错误）
+	 */
+	public static final int CLIENT_INVALID_PARAM = -400;
+	/**
+	 *  over client threshold（超过server端的限流阈值）
+	 */
+	public static final int CLIENT_OVER_THRESHOLD = -503;
+
+	
+	/**
+	 * server error code 
+	 * 400 403 throw exception to user
+	 * 500 502 503 change ip and retry
+	 */
+	
+	/**
+	 *  invalid param（参数错误）
+	 */
+	public static final int INVALID_PARAM = 400;
+	/**
+	 *  no right（鉴权失败）
+	 */
+	public static final int NO_RIGHT = 403;
+	/**
+	 *  conflict（写并发冲突）
+	 */
+	public static final int CONFLICT = 409;
+	/**
+	 *  server error（server异常，如超时）
+	 */
+	public static final int SERVER_ERROR = 500;
+	/**
+	 *  bad gateway（路由异常，如nginx后面的Server挂掉）
+	 */
+	public static final int BAD_GATEWAY = 502;
+	/**
+	 *  over threshold（超过server端的限流阈值）
+	 */
+	public static final int OVER_THRESHOLD = 503;
+	
+
+}

client/src/main/java/com/alibaba/nacos/api/naming/NamingFactory.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.naming;
+
+import java.util.Properties;
+
+import com.alibaba.nacos.client.naming.NacosNamingService;
+
+/**
+ * @author dungu.zpf
+ */
+public class NamingFactory {
+
+	public static NamingService createNamingService(String serverList) {
+		return new NacosNamingService(serverList);
+	}
+
+	public static NamingService createNamingService(Properties properties) {
+		return new NacosNamingService(properties);
+	}
+}

client/src/main/java/com/alibaba/nacos/api/naming/NamingService.java

@@ -0,0 +1,176 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.naming;
+
+import java.util.List;
+
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.api.naming.listener.EventListener;
+import com.alibaba.nacos.api.naming.pojo.Instance;
+
+/**
+ * @author dungu.zpf
+ */
+public interface NamingService {
+
+    /**
+     * Register a instance to service
+     *
+     * @param serviceName name of service
+     * @param ip          instance ip
+     * @param port        instance port
+     * @throws NacosException
+     */
+    void registerInstance(String serviceName, String ip, int port) throws NacosException;
+
+    /**
+     * Register a instance to service with specified cluster name
+     *
+     * @param serviceName name of service
+     * @param ip          instance ip
+     * @param port        instance port
+     * @param clusterName instance cluster name
+     * @throws NacosException
+     */
+    void registerInstance(String serviceName, String ip, int port, String clusterName) throws NacosException;
+
+    /**
+     * Register a instance to service with specified instance properties
+     *
+     * @param serviceName name of service
+     * @param instance    instance to register
+     * @throws NacosException
+     */
+    void registerInstance(String serviceName, Instance instance) throws NacosException;
+
+    /**
+     * Deregister instance from a service
+     *
+     * @param serviceName name of service
+     * @param ip          instance ip
+     * @param port        instance port
+     * @throws NacosException
+     */
+    void deregisterInstance(String serviceName, String ip, int port) throws NacosException;
+
+    /**
+     * Deregister instance with specified cluster name from a service
+     *
+     * @param serviceName name of service
+     * @param ip          instance ip
+     * @param port        instance port
+     * @param clusterName     instance cluster name
+     * @throws NacosException
+     */
+    void deregisterInstance(String serviceName, String ip, int port, String clusterName) throws NacosException;
+
+    /**
+     * Get all instances of a service
+     *
+     * @param serviceName name of service
+     * @return A list of instance
+     * @throws NacosException
+     */
+    List<Instance> getAllInstances(String serviceName) throws NacosException;
+
+    /**
+     * Get all instances within specified clusters of a service
+     *
+     * @param serviceName name of service
+     * @param clusters    list of cluster
+     * @return A list of qualified instance
+     * @throws NacosException
+     */
+    List<Instance> getAllInstances(String serviceName, List<String> clusters) throws NacosException;
+
+    /**
+     * Get qualified instances of service
+     *
+     * @param serviceName name of service
+     * @param healthy     a flag to indicate returning healthy or unhealthy instances
+     * @return A qualified list of instance
+     * @throws NacosException
+     */
+    List<Instance> selectInstances(String serviceName, boolean healthy) throws NacosException;
+
+    /**
+     * Get qualified instances within specified clusters of service
+     *
+     * @param serviceName name of service
+     * @param clusters    list of cluster
+     * @param healthy     a flag to indicate returning healthy or unhealthy instances
+     * @return A qualified list of instance
+     * @throws NacosException
+     */
+    List<Instance> selectInstances(String serviceName, List<String> clusters, boolean healthy) throws NacosException;
+
+    /**
+     * Select one healthy instance of service using predefined load balance strategy
+     *
+     * @param serviceName name of service
+     * @return qualified instance
+     * @throws NacosException
+     */
+    Instance selectOneHealthyInstance(String serviceName) throws NacosException;
+
+    /**
+     * Select one healthy instance of service using predefined load balance strategy
+     *
+     * @param serviceName name of service
+     * @param clusters    a list of clusters should the instance belongs to
+     * @return qualified instance
+     * @throws NacosException
+     */
+    Instance selectOneHealthyInstance(String serviceName, List<String> clusters) throws NacosException;
+
+    /**
+     * Subscribe service to receive events of instances alteration
+     *
+     * @param serviceName name of service
+     * @param listener    event listener
+     * @throws NacosException
+     */
+    void subscribe(String serviceName, EventListener listener) throws NacosException;
+
+    /**
+     * Subscribe service to receive events of instances alteration
+     *
+     * @param serviceName name of service
+     * @param clusters    list of cluster
+     * @param listener    event listener
+     * @throws NacosException
+     */
+    void subscribe(String serviceName, List<String> clusters, EventListener listener) throws NacosException;
+
+    /**
+     * Unsubscribe event listener of service
+     *
+     * @param serviceName name of service
+     * @param listener    event listener
+     * @throws NacosException
+     */
+    void unsubscribe(String serviceName, EventListener listener) throws NacosException;
+
+    /**
+     * Unsubscribe event listener of service
+     *
+     * @param serviceName name of service
+     * @param clusters    list of cluster
+     * @param listener    event listener
+     * @throws NacosException
+     */
+    void unsubscribe(String serviceName, List<String> clusters, EventListener listener) throws NacosException;
+}

client/src/main/java/com/alibaba/nacos/api/naming/listener/Event.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.naming.listener;
+
+/**
+ * event interface
+ * @author dungu.zpf
+ */
+public interface Event {
+}

client/src/main/java/com/alibaba/nacos/api/naming/listener/EventListener.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.naming.listener;
+
+/**
+ * event listener 
+ * @author Nacos
+ *
+ */
+public interface EventListener {
+	/**
+	 * callback event
+	 * @param event
+	 */
+    void onEvent(Event event);
+}

client/src/main/java/com/alibaba/nacos/api/naming/listener/NamingEvent.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.naming.listener;
+
+import java.util.List;
+
+import com.alibaba.nacos.api.naming.pojo.Instance;
+
+/**
+ * @author dungu.zpf
+ */
+public class NamingEvent implements Event {
+
+    private String serviceName;
+
+    private List<Instance> instances;
+
+    public NamingEvent(String serviceName, List<Instance> instances) {
+        this.serviceName = serviceName;
+        this.instances = instances;
+    }
+
+    public String getServiceName() {
+        return serviceName;
+    }
+
+    public void setServiceName(String serviceName) {
+        this.serviceName = serviceName;
+    }
+
+    public List<Instance> getInstances() {
+        return instances;
+    }
+
+    public void setInstances(List<Instance> instances) {
+        this.instances = instances;
+    }
+}

client/src/main/java/com/alibaba/nacos/api/naming/pojo/AbstractHealthChecker.java

@@ -0,0 +1,179 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.naming.pojo;
+
+import com.alibaba.nacos.client.naming.utils.StringUtils;
+
+import java.util.Objects;
+
+/**
+ * @author dungu.zpf
+ */
+public abstract class AbstractHealthChecker implements Cloneable {
+
+    protected String type = "unknown";
+
+    public String getType() {
+        return type;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+
+    public static class Http extends AbstractHealthChecker {
+        public static final String TYPE = "HTTP";
+
+        private String path = StringUtils.EMPTY;
+        private String headers = StringUtils.EMPTY;
+
+        private int expectedResponseCode = 200;
+
+        public Http() {
+            this.type = TYPE;
+        }
+
+        public int getExpectedResponseCode() {
+            return expectedResponseCode;
+        }
+
+        public void setExpectedResponseCode(int expectedResponseCode) {
+            this.expectedResponseCode = expectedResponseCode;
+        }
+
+        public String getPath() {
+            return path;
+        }
+
+        public void setPath(String path) {
+            this.path = path;
+        }
+
+        public String getHeaders() {
+            return headers;
+        }
+
+        public void setHeaders(String headers) {
+            this.headers = headers;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(path, headers, expectedResponseCode);
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (!(obj instanceof Http)) {
+                return false;
+            }
+
+            Http other = (Http) obj;
+
+            if (!StringUtils.equals(type, other.getType())) {
+                return false;
+            }
+
+            if (!StringUtils.equals(path, other.getPath())) {
+                return false;
+            }
+            if (!StringUtils.equals(headers, other.getHeaders())) {
+                return false;
+            }
+            return expectedResponseCode == other.getExpectedResponseCode();
+        }
+    }
+
+    public static class Tcp extends AbstractHealthChecker {
+        public static final String TYPE = "TCP";
+
+        public Tcp() {
+            this.type = TYPE;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(TYPE);
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            return obj instanceof Tcp;
+
+        }
+    }
+
+    public static class Mysql extends AbstractHealthChecker {
+        public static final String TYPE = "MYSQL";
+
+        private String user;
+        private String pwd;
+        private String cmd;
+
+        public Mysql() {
+            this.type = TYPE;
+        }
+
+        public String getCmd() {
+            return cmd;
+        }
+
+        public String getPwd() {
+            return pwd;
+        }
+
+        public String getUser() {
+            return user;
+        }
+
+        public void setUser(String user) {
+            this.user = user;
+        }
+
+        public void setCmd(String cmd) {
+            this.cmd = cmd;
+        }
+
+        public void setPwd(String pwd) {
+            this.pwd = pwd;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(user, pwd, cmd);
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (!(obj instanceof Mysql)) {
+                return false;
+            }
+
+            Mysql other = (Mysql) obj;
+
+            if (!StringUtils.equals(user, other.getUser())) {
+                return false;
+            }
+
+            if (!StringUtils.equals(pwd, other.getPwd())) {
+                return false;
+            }
+
+            return StringUtils.equals(cmd, other.getCmd());
+
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/api/naming/pojo/Cluster.java

@@ -0,0 +1,124 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.naming.pojo;
+
+import com.alibaba.nacos.client.naming.utils.StringUtils;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * @author dungu.zpf
+ */
+public class Cluster {
+
+    /**
+     * Name of belonging service
+     */
+    private String serviceName;
+
+    /**
+     * Name of cluster
+     */
+    private String name = StringUtils.EMPTY;
+
+    /**
+     * Health check config of this cluster
+     */
+    private AbstractHealthChecker healthChecker = new AbstractHealthChecker.Tcp();
+
+    /**
+     * Default registered port for instances in this cluster.
+     */
+    private int defaultPort = 80;
+
+    /**
+     * Default health check port of instances in this cluster.
+     */
+    private int defaultCheckPort = 80;
+
+    /**
+     * Whether or not use instance port to do health check.
+     */
+    private boolean useIPPort4Check = true;
+
+
+    private Map<String, String> metadata = new HashMap<>();
+
+    public Cluster() {
+
+    }
+
+    public Cluster(String clusterName) {
+        this.name = clusterName;
+    }
+
+    public String getServiceName() {
+        return serviceName;
+    }
+
+    public void setServiceName(String serviceName) {
+        this.serviceName = serviceName;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public AbstractHealthChecker getHealthChecker() {
+        return healthChecker;
+    }
+
+    public void setHealthChecker(AbstractHealthChecker healthChecker) {
+        this.healthChecker = healthChecker;
+    }
+
+    public int getDefaultPort() {
+        return defaultPort;
+    }
+
+    public void setDefaultPort(int defaultPort) {
+        this.defaultPort = defaultPort;
+    }
+
+    public int getDefaultCheckPort() {
+        return defaultCheckPort;
+    }
+
+    public void setDefaultCheckPort(int defaultCheckPort) {
+        this.defaultCheckPort = defaultCheckPort;
+    }
+
+    public boolean isUseIPPort4Check() {
+        return useIPPort4Check;
+    }
+
+    public void setUseIPPort4Check(boolean useIPPort4Check) {
+        this.useIPPort4Check = useIPPort4Check;
+    }
+
+    public Map<String, String> getMetadata() {
+        return metadata;
+    }
+
+    public void setMetadata(Map<String, String> metadata) {
+        this.metadata = metadata;
+    }
+}

client/src/main/java/com/alibaba/nacos/api/naming/pojo/Instance.java

@@ -0,0 +1,166 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.naming.pojo;
+
+import com.alibaba.fastjson.JSON;
+import com.alibaba.fastjson.annotation.JSONField;
+import com.alibaba.nacos.client.naming.utils.StringUtils;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * @author dungu.zpf
+ */
+public class Instance {
+
+    /**
+     * Unique ID of this instance.
+     */
+    private String instanceId;
+
+    /**
+     * Instance ip
+     */
+    private String ip;
+
+    /**
+     * Instance port
+     */
+    private int port;
+
+    /**
+     * Instance weight
+     */
+    private double weight = 1.0D;
+
+    /**
+     * Instance health status
+     */
+    @JSONField(name = "valid")
+    private boolean healthy = true;
+
+    /**
+     * Cluster information of instance
+     */
+    @JSONField(serialize = false)
+    private Cluster cluster = new Cluster();
+
+    /**
+     * Service information of instance
+     */
+    @JSONField(serialize = false)
+    private Service service;
+
+    /**
+     * User extended attributes
+     */
+    private Map<String, String> metadata = new HashMap<>();
+
+    public String getInstanceId() {
+        return instanceId;
+    }
+
+    public void setInstanceId(String instanceId) {
+        this.instanceId = instanceId;
+    }
+
+    public String getIp() {
+        return ip;
+    }
+
+    public void setIp(String ip) {
+        this.ip = ip;
+    }
+
+    public int getPort() {
+        return port;
+    }
+
+    public void setPort(int port) {
+        this.port = port;
+    }
+
+    public double getWeight() {
+        return weight;
+    }
+
+    public void setWeight(double weight) {
+        this.weight = weight;
+    }
+
+    public boolean isHealthy() {
+        return healthy;
+    }
+
+    public void setHealthy(boolean healthy) {
+        this.healthy = healthy;
+    }
+
+    public Cluster getCluster() {
+        return cluster;
+    }
+
+    public void setCluster(Cluster cluster) {
+        this.cluster = cluster;
+    }
+
+    public Service getService() {
+        return service;
+    }
+
+    public void setService(Service service) {
+        this.service = service;
+    }
+
+    public Map<String, String> getMetadata() {
+        return metadata;
+    }
+
+    public void setMetadata(Map<String, String> metadata) {
+        this.metadata = metadata;
+    }
+
+    public void addMetadata(String key, String value) {
+        this.metadata.put(key, value);
+    }
+
+    @Override
+    public String toString() {
+        return JSON.toJSONString(this);
+    }
+
+    public String toInetAddr() {
+        return ip + ":" + port;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (!(obj instanceof Instance)) {
+            return false;
+        }
+
+        Instance host = (Instance) obj;
+
+        return StringUtils.equals(toString(), host.toString());
+    }
+
+    @Override
+    public int hashCode() {
+        return toString().hashCode();
+    }
+
+}

client/src/main/java/com/alibaba/nacos/api/naming/pojo/Service.java

@@ -0,0 +1,108 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.api.naming.pojo;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * @author dungu.zpf
+ */
+public class Service {
+
+    /**
+     * Service name
+     */
+    private String name;
+
+    /**
+     * Protect threshold
+     */
+    private float protectThreshold = 0.0F;
+
+    /**
+     * Application name of this service
+     */
+    private String app;
+
+    /**
+     * Service group which is meant to classify services into different sets.
+     */
+    private String group;
+
+    /**
+     * Health check mode.
+     */
+    private String healthCheckMode;
+
+    public Service(String name) {
+        this.name = name;
+    }
+
+    private Map<String, String> metadata = new HashMap<>();
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getHealthCheckMode() {
+        return healthCheckMode;
+    }
+
+    public void setHealthCheckMode(String healthCheckMode) {
+        this.healthCheckMode = healthCheckMode;
+    }
+
+    public float getProtectThreshold() {
+        return protectThreshold;
+    }
+
+    public void setProtectThreshold(float protectThreshold) {
+        this.protectThreshold = protectThreshold;
+    }
+
+    public String getApp() {
+        return app;
+    }
+
+    public void setApp(String app) {
+        this.app = app;
+    }
+
+    public String getGroup() {
+        return group;
+    }
+
+    public void setGroup(String group) {
+        this.group = group;
+    }
+
+    public Map<String, String> getMetadata() {
+        return metadata;
+    }
+
+    public void setMetadata(Map<String, String> metadata) {
+        this.metadata = metadata;
+    }
+
+    public void addMetadata(String key, String value) {
+        this.metadata.put(key, value);
+    }
+}

client/src/main/java/com/alibaba/nacos/client/config/NacosConfigService.java

@@ -0,0 +1,267 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Properties;
+
+import com.alibaba.nacos.api.PropertyKeyConst;
+import com.alibaba.nacos.api.config.ConfigService;
+import com.alibaba.nacos.api.config.listener.Listener;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.client.config.common.Constants;
+import com.alibaba.nacos.client.config.filter.impl.ConfigFilterChainManager;
+import com.alibaba.nacos.client.config.filter.impl.ConfigRequest;
+import com.alibaba.nacos.client.config.filter.impl.ConfigResponse;
+import com.alibaba.nacos.client.config.impl.ClientWorker;
+import com.alibaba.nacos.client.config.impl.LocalConfigInfoProcessor;
+import com.alibaba.nacos.client.config.impl.ServerHttpAgent;
+import com.alibaba.nacos.client.config.impl.HttpSimpleClient.HttpResult;
+import com.alibaba.nacos.client.config.utils.ContentUtils;
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.config.utils.ParamUtils;
+import com.alibaba.nacos.client.config.utils.TenantUtil;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+/**
+ * Config Impl
+ * @author Nacos
+ *
+ */
+@SuppressWarnings("PMD.ServiceOrDaoClassShouldEndWithImplRule")
+public class NacosConfigService implements ConfigService {
+
+	final static public Logger log = LogUtils.logger(NacosConfigService.class);
+	public final long POST_TIMEOUT = 3000L;
+	/**
+	 * http agent
+	 */
+	private ServerHttpAgent agent;
+	/**
+	 * longpulling
+	 */
+	private ClientWorker worker;
+	private String namespace;
+	private String encode;
+	private ConfigFilterChainManager configFilterChainManager = new ConfigFilterChainManager();
+
+	public NacosConfigService(Properties properties) throws NacosException {
+		String encodeTmp = properties.getProperty(PropertyKeyConst.ENCODE);
+		if (StringUtils.isBlank(encodeTmp)) {
+			encode = Constants.ENCODE;
+		} else {
+			encode = encodeTmp.trim();
+		}
+		String namespaceTmp = properties.getProperty(PropertyKeyConst.NAMESPACE);
+		if (StringUtils.isBlank(namespaceTmp)) {
+			namespace = TenantUtil.getUserTenant();
+			properties.put(PropertyKeyConst.NAMESPACE, namespace);
+		} else {
+			namespace = namespaceTmp;
+			properties.put(PropertyKeyConst.NAMESPACE, namespace);
+		}
+		agent = new ServerHttpAgent(properties);
+		agent.start();
+		worker = new ClientWorker(agent, configFilterChainManager);
+	}
+
+	@Override
+	public String getConfig(String dataId, String group, long timeoutMs) throws NacosException {
+		return getConfigInner(namespace, dataId, group, timeoutMs);
+	}
+
+	@Override
+	public void addListener(String dataId, String group, Listener listener) throws NacosException {
+		worker.addTenantListeners(dataId, group, Arrays.asList(listener));
+	}
+
+	@Override
+	public boolean publishConfig(String dataId, String group, String content) throws NacosException {
+		return publishConfigInner(namespace, dataId, group, null, null, null, content);
+	}
+
+	@Override
+	public boolean removeConfig(String dataId, String group) throws NacosException {
+		return removeConfigInner(namespace, dataId, group, null);
+	}
+
+	@Override
+	public void removeListener(String dataId, String group, Listener listener) {
+		worker.removeTenantListener(dataId, group, listener);
+	}
+
+	private String getConfigInner(String tenant, String dataId, String group, long timeoutMs) throws NacosException {
+		group = null2defaultGroup(group);
+		ParamUtils.checkKeyParam(dataId, group);
+		ConfigResponse cr = new ConfigResponse();
+
+		cr.setDataId(dataId);
+		cr.setTenant(tenant);
+		cr.setGroup(group);
+
+		// 优先使用本地配置
+		String content = LocalConfigInfoProcessor.getFailover(agent.getName(), dataId, group, tenant);
+		if (content != null) {
+			log.warn(agent.getName(), "[get-config] get failover ok, dataId={}, group={}, tenant={}, config={}", dataId,
+					group, tenant, ContentUtils.truncateContent(content));
+			cr.setContent(content);
+			configFilterChainManager.doFilter(null, cr);
+			content = cr.getContent();
+			return content;
+		}
+
+		try {
+			content = worker.getServerConfig(dataId, group, tenant, timeoutMs);
+			cr.setContent(content);
+			configFilterChainManager.doFilter(null, cr);
+			content = cr.getContent();
+			return content;
+		} catch (NacosException ioe) {
+			if (NacosException.NO_RIGHT == ioe.getErrCode()) {
+				throw ioe;
+			}
+			log.warn("NACOS-0003",
+					LoggerHelper.getErrorCodeStr("NACOS", "NACOS-0003", "环境问题", "get from server error"));
+			log.warn(agent.getName(), "[get-config] get from server error, dataId={}, group={}, tenant={}, msg={}",
+					dataId, group, tenant, ioe.toString());
+		}
+
+		log.warn(agent.getName(), "[get-config] get snapshot ok, dataId={}, group={}, tenant={}, config={}", dataId,
+				group, tenant, ContentUtils.truncateContent(content));
+		content = LocalConfigInfoProcessor.getSnapshot(agent.getName(), dataId, group, tenant);
+		cr.setContent(content);
+		configFilterChainManager.doFilter(null, cr);
+		content = cr.getContent();
+		return content;
+	}
+
+	private String null2defaultGroup(String group) {
+		return (null == group) ? Constants.DEFAULT_GROUP : group.trim();
+	}
+
+	private boolean removeConfigInner(String tenant, String dataId, String group, String tag) throws NacosException {
+		group = null2defaultGroup(group);
+		ParamUtils.checkKeyParam(dataId, group);
+		String url = Constants.CONFIG_CONTROLLER_PATH;
+		List<String> params = new ArrayList<String>();
+		params.add("dataId");
+		params.add(dataId);
+		params.add("group");
+		params.add(group);
+		if (StringUtils.isNotEmpty(tenant)) {
+			params.add("tenant");
+			params.add(tenant);
+		}
+		if (StringUtils.isNotEmpty(tag)) {
+			params.add("tag");
+			params.add(tag);
+		}
+		HttpResult result = null;
+		try {
+			result = agent.httpDelete(url, null, params, encode, POST_TIMEOUT);
+		} catch (IOException ioe) {
+			log.warn("[remove] error, " + dataId + ", " + group + ", " + tenant + ", msg: " + ioe.toString());
+			return false;
+		}
+
+		if (HttpURLConnection.HTTP_OK == result.code) {
+			log.info(agent.getName(), "[remove] ok, dataId={}, group={}, tenant={}", dataId, group, tenant);
+			return true;
+		} else if (HttpURLConnection.HTTP_FORBIDDEN == result.code) {
+			log.warn(agent.getName(), "[remove] error, dataId={}, group={}, tenant={}, code={}, msg={}", dataId, group,
+					tenant, result.code, result.content);
+			throw new NacosException(result.code, result.content);
+		} else {
+			log.warn(agent.getName(), "[remove] error, dataId={}, group={}, tenant={}, code={}, msg={}", dataId, group,
+					tenant, result.code, result.content);
+			return false;
+		}
+	}
+
+	private boolean publishConfigInner(String tenant, String dataId, String group, String tag, String appName,
+			String betaIps, String content) throws NacosException {
+		group = null2defaultGroup(group);
+		ParamUtils.checkParam(dataId, group, content);
+
+		ConfigRequest cr = new ConfigRequest();
+		cr.setDataId(dataId);
+		cr.setTenant(tenant);
+		cr.setGroup(group);
+		cr.setContent(content);
+		configFilterChainManager.doFilter(cr, null);
+		content = cr.getContent();
+
+		String url = Constants.CONFIG_CONTROLLER_PATH;
+		List<String> params = new ArrayList<String>();
+		params.add("dataId");
+		params.add(dataId);
+		params.add("group");
+		params.add(group);
+		params.add("content");
+		params.add(content);
+		if (StringUtils.isNotEmpty(tenant)) {
+			params.add("tenant");
+			params.add(tenant);
+		}
+		if (StringUtils.isNotEmpty(appName)) {
+			params.add("appName");
+			params.add(appName);
+		}
+		if (StringUtils.isNotEmpty(tag)) {
+			params.add("tag");
+			params.add(tag);
+		}
+
+		List<String> headers = new ArrayList<String>();
+		if (StringUtils.isNotEmpty(betaIps)) {
+			headers.add("betaIps");
+			headers.add(betaIps);
+		}
+
+		HttpResult result = null;
+		try {
+			result = agent.httpPost(url, headers, params, encode, POST_TIMEOUT);
+		} catch (IOException ioe) {
+			log.warn("NACOS-0006",
+					LoggerHelper.getErrorCodeStr("NACOS", "NACOS-0006", "环境问题", "[publish-single] exception"));
+			log.warn(agent.getName(), "[publish-single] exception, dataId={}, group={}, msg={}", dataId, group,
+					ioe.toString());
+			return false;
+		}
+
+		if (HttpURLConnection.HTTP_OK == result.code) {
+			log.info(agent.getName(), "[publish-single] ok, dataId={}, group={}, tenant={}, config={}", dataId, group,
+					tenant, ContentUtils.truncateContent(content));
+			return true;
+		} else if (HttpURLConnection.HTTP_FORBIDDEN == result.code) {
+			log.warn(agent.getName(), "[publish-single] error, dataId={}, group={}, tenant={}, code={}, msg={}", dataId,
+					group, tenant, result.code, result.content);
+			throw new NacosException(result.code, result.content);
+		} else {
+			log.warn(agent.getName(), "[publish-single] error, dataId={}, group={}, tenant={}, code={}, msg={}", dataId,
+					group, tenant, result.code, result.content);
+			return false;
+		}
+
+	}
+
+}

client/src/main/java/com/alibaba/nacos/client/config/common/Constants.java

@@ -0,0 +1,127 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.common;
+
+/**
+ * Constant
+ * 
+ * @author Nacos
+ *
+ */
+public class Constants {
+
+	public static final String CLIENT_VERSION_HEADER = "Client-Version";
+
+	public static final String CLIENT_VERSION = "3.0.0";
+
+	public static int DATA_IN_BODY_VERSION = 204;
+
+	public static final String DEFAULT_GROUP = "DEFAULT_GROUP";
+
+	public static final String APPNAME = "AppName";
+
+	public static final String UNKNOWN_APP = "UnknownApp";
+
+	public static final String DEFAULT_DOMAINNAME = "commonconfig.config-host.taobao.com";
+
+	public static final String DAILY_DOMAINNAME = "commonconfig.taobao.net";
+
+	public static final int DEFAULT_PORT = 8080;
+
+	public static final String NULL = "";
+
+	public static final String DATAID = "dataId";
+
+	public static final String GROUP = "group";
+
+	public static final String LAST_MODIFIED = "Last-Modified";
+
+	public static final String ACCEPT_ENCODING = "Accept-Encoding";
+
+	public static final String CONTENT_ENCODING = "Content-Encoding";
+
+	public static final String PROBE_MODIFY_REQUEST = "Listening-Configs";
+
+	public static final String PROBE_MODIFY_RESPONSE = "Probe-Modify-Response";
+
+	public static final String PROBE_MODIFY_RESPONSE_NEW = "Probe-Modify-Response-New";
+
+	public static final String USE_ZIP = "true";
+
+	public static final String CONTENT_MD5 = "Content-MD5";
+
+	public static final String CONFIG_VERSION = "Config-Version";
+
+	public static final String IF_MODIFIED_SINCE = "If-Modified-Since";
+
+	public static final String SPACING_INTERVAL = "client-spacing-interval";
+
+	public static final String BASE_PATH = "/v1/cs";
+
+	public static final String CONFIG_CONTROLLER_PATH = BASE_PATH + "/configs";
+
+	/**
+	 * second
+	 */
+	public static final int ASYNC_UPDATE_ADDRESS_INTERVAL = 300;
+
+	/**
+	 * second
+	 */
+	public static final int POLLING_INTERVAL_TIME = 15;
+
+	/**
+	 *  millisecond
+	 */
+	public static final int ONCE_TIMEOUT = 2000;
+
+	/**
+	 *  millisecond
+	 */
+	public static final int CONN_TIMEOUT = 2000;
+
+	/**
+	 *  millisecond
+	 */
+	public static final int SO_TIMEOUT = 60000;
+
+	/**
+	 *  millisecond
+	 */
+	public static final int RECV_WAIT_TIMEOUT = ONCE_TIMEOUT * 5;
+
+	public static final String ENCODE = "UTF-8";
+
+	public static final String MAP_FILE = "map-file.js";
+
+	public static final int FLOW_CONTROL_THRESHOLD = 20;
+
+	public static final int FLOW_CONTROL_SLOT = 10;
+
+	public static final int FLOW_CONTROL_INTERVAL = 1000;
+
+	public static final String LINE_SEPARATOR = Character.toString((char) 1);
+
+	public static final String WORD_SEPARATOR = Character.toString((char) 2);
+
+	public static final String LONGPULLING_LINE_SEPARATOR = "\r\n";
+
+	public static final String CLIENT_APPNAME_HEADER = "Client-AppName";
+	public static final String CLIENT_REQUEST_TS_HEADER = "Client-RequestTS";
+	public static final String CLIENT_REQUEST_TOKEN_HEADER = "Client-RequestToken";
+
+	public static final int ATOMIC_MAX_SIZE = 1000;
+}

client/src/main/java/com/alibaba/nacos/client/config/common/GroupKey.java

@@ -0,0 +1,123 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.common;
+
+import com.alibaba.nacos.client.utils.StringUtils;
+
+/**
+ * Synthesize the form of dataId+groupId. Escapes reserved characters in dataId
+ * and groupId.
+ * 
+ * @author Nacos
+ */
+public class GroupKey {
+
+    static public String getKey(String dataId, String group) {
+        StringBuilder sb = new StringBuilder();
+        urlEncode(dataId, sb);
+        sb.append('+');
+        urlEncode(group, sb);
+        return sb.toString();
+    }
+
+	static public String getKeyTenant(String dataId, String group, String tenant) {
+		StringBuilder sb = new StringBuilder();
+		urlEncode(dataId, sb);
+		sb.append('+');
+		urlEncode(group, sb);
+		if (StringUtils.isNotEmpty(tenant)) {
+			sb.append('+');
+			urlEncode(tenant, sb);
+		}
+		return sb.toString();
+	}
+    
+	static public String getKey(String dataId, String group, String datumStr) {
+		StringBuilder sb = new StringBuilder();
+		urlEncode(dataId, sb);
+		sb.append('+');
+		urlEncode(group, sb);
+		sb.append('+');
+		urlEncode(datumStr, sb);
+		return sb.toString();
+	}
+    
+    static public String[] parseKey(String groupKey) {
+        StringBuilder sb = new StringBuilder();
+        String dataId = null;
+        String group = null;
+        String tenant = null;
+
+        for (int i = 0; i < groupKey.length(); ++i) {
+            char c = groupKey.charAt(i);
+            if ('+' == c) {
+				if (null == dataId) {
+					dataId = sb.toString();
+					sb.setLength(0);
+				} else if (null == group) {
+					group = sb.toString();
+					sb.setLength(0);
+				} else {
+					throw new IllegalArgumentException("invalid groupkey:" + groupKey);
+				}
+            } else if ('%' == c) {
+                char next = groupKey.charAt(++i);
+                char nextnext = groupKey.charAt(++i);
+                if ('2' == next && 'B' == nextnext) {
+                    sb.append('+');
+                } else if ('2' == next && '5' == nextnext) {
+                    sb.append('%');
+                } else {
+                    throw new IllegalArgumentException("invalid groupkey:" + groupKey);
+                }
+            } else {
+                sb.append(c);
+            }
+        }
+        
+		if (StringUtils.isBlank(group)) {
+			group = sb.toString();
+			if (group.length() == 0) {
+				throw new IllegalArgumentException("invalid groupkey:" + groupKey);
+			}
+		} else {
+			tenant = sb.toString();
+			if (group.length() == 0) {
+				throw new IllegalArgumentException("invalid groupkey:" + groupKey);
+			}
+		}
+       
+        return new String[] { dataId, group, tenant };
+    }
+    
+    /**
+     * + -> %2B
+     * % -> %25
+     */
+    static void urlEncode(String str, StringBuilder sb) {
+        for (int idx = 0; idx < str.length(); ++idx) {
+            char c = str.charAt(idx);
+            if ('+' == c) {
+                sb.append("%2B");
+            } else if ('%' == c) {
+                sb.append("%25");
+            } else {
+                sb.append(c);
+            }
+        }
+    }
+
+}

client/src/main/java/com/alibaba/nacos/client/config/filter/impl/ConfigContext.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.filter.impl;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import com.alibaba.nacos.api.config.filter.IConfigContext;
+
+/**
+ * Config Context
+ * 
+ * @author Nacos
+ *
+ */
+public class ConfigContext implements IConfigContext {
+
+	private Map<String, Object> param = new HashMap<String, Object>();
+
+	@Override
+	public Object getParameter(String key) {
+		return param.get(key);
+	}
+
+	@Override
+	public void setParameter(String key, Object value) {
+		param.put(key, value);
+	}
+
+}

client/src/main/java/com/alibaba/nacos/client/config/filter/impl/ConfigFilterChainManager.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.filter.impl;
+
+import java.util.List;
+
+import com.alibaba.nacos.api.config.filter.IConfigFilter;
+import com.alibaba.nacos.api.config.filter.IConfigFilterChain;
+import com.alibaba.nacos.api.config.filter.IConfigRequest;
+import com.alibaba.nacos.api.config.filter.IConfigResponse;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.google.common.collect.Lists;
+
+/**
+ * Config Filter Chain Management
+ * 
+ * @author Nacos
+ *
+ */
+public class ConfigFilterChainManager implements IConfigFilterChain {
+
+	private List<IConfigFilter> filters = Lists.newArrayList();
+
+	public synchronized ConfigFilterChainManager addFilter(IConfigFilter filter) {
+		// 根据order大小顺序插入
+		int i = 0;
+		while (i < this.filters.size()) {
+			IConfigFilter currentValue = this.filters.get(i);
+			if (currentValue.getFilterName().equals(filter.getFilterName())) {
+				break;
+			}
+			if (filter.getOrder() >= currentValue.getOrder() && i < this.filters.size()) {
+				i++;
+			} else {
+				this.filters.add(i, filter);
+				break;
+			}
+		}
+
+		if (i == this.filters.size()) {
+			this.filters.add(i, filter);
+		}
+		return this;
+	}
+	
+
+	@Override
+	public void doFilter(IConfigRequest request, IConfigResponse response) throws NacosException {
+		new VirtualFilterChain(this.filters).doFilter(request, response);
+	}
+
+	private static class VirtualFilterChain implements IConfigFilterChain {
+
+		private final List<? extends IConfigFilter> additionalFilters;
+
+		private int currentPosition = 0;
+
+		public VirtualFilterChain(List<? extends IConfigFilter> additionalFilters) {
+			this.additionalFilters = additionalFilters;
+		}
+
+		@Override
+		public void doFilter(final IConfigRequest request, final IConfigResponse response) throws NacosException {
+			if (this.currentPosition == this.additionalFilters.size()) {
+				return;
+			} else {
+				this.currentPosition++;
+				IConfigFilter nextFilter = this.additionalFilters.get(this.currentPosition - 1);
+				nextFilter.doFilter(request, response, this);
+			}
+		}
+	}
+
+}

client/src/main/java/com/alibaba/nacos/client/config/filter/impl/ConfigRequest.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.filter.impl;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import com.alibaba.nacos.api.config.filter.IConfigContext;
+import com.alibaba.nacos.api.config.filter.IConfigRequest;
+
+/**
+ * Config Request
+ * 
+ * @author Nacos
+ *
+ */
+public class ConfigRequest implements IConfigRequest {
+
+	private Map<String, Object> param = new HashMap<String, Object>();
+
+	private IConfigContext configContext = new ConfigContext();
+
+	public String getTenant() {
+		return (String) param.get("tenant");
+	}
+
+	public void setTenant(String tenant) {
+		param.put("tenant", tenant);
+	}
+
+	public String getDataId() {
+		return (String) param.get("dataId");
+	}
+
+	public void setDataId(String dataId) {
+		param.put("dataId", dataId);
+	}
+
+	public String getGroup() {
+		return (String) param.get("group");
+	}
+
+	public void setGroup(String group) {
+		param.put("group", group);
+	}
+
+	public String getContent() {
+		return (String) param.get("content");
+	}
+
+	public void setContent(String content) {
+		param.put("content", content);
+	}
+
+	@Override
+	public Object getParameter(String key) {
+		return param.get(key);
+	}
+
+	@Override
+	public IConfigContext getConfigContext() {
+		return configContext;
+	}
+
+}

client/src/main/java/com/alibaba/nacos/client/config/filter/impl/ConfigResponse.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.filter.impl;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import com.alibaba.nacos.api.config.filter.IConfigContext;
+import com.alibaba.nacos.api.config.filter.IConfigResponse;
+
+/**
+ * Config Response
+ * 
+ * @author Nacos
+ *
+ */
+public class ConfigResponse implements IConfigResponse {
+
+	private Map<String, Object> param = new HashMap<String, Object>();
+
+	private IConfigContext configContext = new ConfigContext();
+
+	public String getTenant() {
+		return (String) param.get("tenant");
+	}
+
+	public void setTenant(String tenant) {
+		param.put("tenant", tenant);
+	}
+
+	public String getDataId() {
+		return (String) param.get("dataId");
+	}
+
+	public void setDataId(String dataId) {
+		param.put("dataId", dataId);
+	}
+
+	public String getGroup() {
+		return (String) param.get("group");
+	}
+
+	public void setGroup(String group) {
+		param.put("group", group);
+	}
+
+	public String getContent() {
+		return (String) param.get("content");
+	}
+
+	public void setContent(String content) {
+		param.put("content", content);
+	}
+
+	@Override
+	public Object getParameter(String key) {
+		return param.get(key);
+	}
+
+	@Override
+	public IConfigContext getConfigContext() {
+		return configContext;
+	}
+
+}

client/src/main/java/com/alibaba/nacos/client/config/impl/CacheData.java

@@ -0,0 +1,319 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+import com.alibaba.nacos.api.config.listener.AbstractSharedListener;
+import com.alibaba.nacos.api.config.listener.Listener;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.client.config.common.Constants;
+import com.alibaba.nacos.client.config.filter.impl.ConfigFilterChainManager;
+import com.alibaba.nacos.client.config.filter.impl.ConfigResponse;
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.config.utils.MD5;
+import com.alibaba.nacos.client.config.utils.TenantUtil;
+import com.alibaba.nacos.client.logger.Logger;
+
+/**
+ * Listner Management
+ * 
+ * @author Nacos
+ *
+ */
+public class CacheData {
+
+	final static public Logger log = LogUtils.logger(CacheData.class);
+	
+	public boolean isInitializing() {
+		return isInitializing;
+	}
+
+	public void setInitializing(boolean isInitializing) {
+		this.isInitializing = isInitializing;
+	}
+
+	public String getMd5() {
+        return md5;
+    }
+    
+	public String getTenant() {
+		return tenant;
+	}
+
+    public String getContent() {
+        return content;
+    }
+    
+    public void setContent(String newContent) {
+        this.content = newContent;
+        this.md5 = getMd5String(content);
+    }
+    
+	/**
+	 * Add listener
+	 * 
+	 * @param listener
+	 *            listener
+	 */
+	public void addListener(Listener listener) {
+		if (null == listener) {
+			throw new IllegalArgumentException("listener is null");
+		}
+		ManagerListenerWrap wrap = new ManagerListenerWrap(listener);
+		if (listeners.addIfAbsent(wrap)) {
+			log.info(name, "[add-listener] ok, tenant={}, dataId={}, group={}, cnt={}", tenant, dataId, group,
+					listeners.size());
+		}
+	}
+    
+    public void removeListener(Listener listener) {
+        if (null == listener) {
+            throw new IllegalArgumentException("listener is null");
+        }
+        ManagerListenerWrap wrap = new ManagerListenerWrap(listener);
+        if (listeners.remove(wrap)) {
+            log.info(name, "[remove-listener] ok, dataId={}, group={}, cnt={}", dataId, group, listeners.size());
+        }
+    }
+    
+    /**
+     * 返回监听器列表上的迭代器，只读。保证不返回NULL。
+     */
+    public List<Listener> getListeners() {
+        List<Listener> result = new ArrayList<Listener>();
+        for (ManagerListenerWrap wrap : listeners) {
+            result.add(wrap.listener);
+        }
+        return result;
+    }
+
+    
+    public long getLocalConfigInfoVersion() {
+        return localConfigLastModified;
+    }
+    public void setLocalConfigInfoVersion(long localConfigLastModified) {
+        this.localConfigLastModified = localConfigLastModified;
+    }
+
+
+    public boolean isUseLocalConfigInfo() {
+        return isUseLocalConfig;
+    }
+    public void setUseLocalConfigInfo(boolean useLocalConfigInfo) {
+        this.isUseLocalConfig = useLocalConfigInfo;
+        if (!useLocalConfigInfo) {
+            localConfigLastModified = -1;
+        }
+    }
+    
+    public int getTaskId() {
+		return taskId;
+	}
+
+	public void setTaskId(int taskId) {
+		this.taskId = taskId;
+	}
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((dataId == null) ? 0 : dataId.hashCode());
+        result = prime * result + ((group == null) ? 0 : group.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (null == obj || obj.getClass() != getClass()) {
+            return false;
+        }
+        if (this == obj) {
+            return true;
+        }
+        CacheData other = (CacheData) obj;
+        return dataId.equals(other.dataId) && group.equals(other.group);
+    }
+
+    @Override
+    public String toString() {
+        return "CacheData [" + dataId + ", " + group + "]";
+    }
+    
+    void checkListenerMd5() {
+        for (ManagerListenerWrap wrap : listeners) {
+            if (!md5.equals(wrap.lastCallMd5)) {
+                safeNotifyListener(dataId, group, content, md5, wrap);
+            }
+        }
+    }
+    
+    private void safeNotifyListener(final String dataId, final String group, final String content,
+            final String md5, final ManagerListenerWrap listenerWrap) {
+        final Listener listener = listenerWrap.listener;
+        
+        Runnable job = new Runnable() {
+            public void run() {
+            	ClassLoader myClassLoader = Thread.currentThread().getContextClassLoader();
+            	ClassLoader appClassLoader= listener.getClass().getClassLoader();
+                try {
+                    if(listener instanceof AbstractSharedListener){
+                        AbstractSharedListener adapter = (AbstractSharedListener) listener;
+                        adapter.fillContext(dataId, group);
+                        log.info(name, "[notify-context] dataId={}, group={}, md5={}", dataId, group, md5);
+                    }
+                    // 执行回调之前先将线程classloader设置为具体webapp的classloader，以免回调方法中调用spi接口是出现异常或错用（多应用部署才会有该问题）。
+                    Thread.currentThread().setContextClassLoader(appClassLoader);
+                    
+					ConfigResponse cr = new ConfigResponse();
+					cr.setDataId(dataId);
+					cr.setGroup(group);
+					cr.setContent(content);
+					configFilterChainManager.doFilter(null, cr);
+					String contentTmp = cr.getContent();
+					listener.receiveConfigInfo(contentTmp);
+					listenerWrap.lastCallMd5 = md5;
+					log.info(
+							name,
+							"[notify-ok] dataId={}, group={}, md5={}, listener={} ",
+							dataId, group, md5, listener);
+				} catch (NacosException de) {
+					log.error(name, "NACOS-XXXX",
+							"[notify-error] dataId={}, group={}, md5={}, listener={} errCode={} errMsg={}", dataId,
+							group, md5, listener, de.getErrCode(), de.getErrMsg());
+				} catch (Throwable t) {
+					log.error(name, "NACOS-XXXX",
+							"[notify-error] dataId={}, group={}, md5={}, listener={} tx={}", dataId, group, md5,
+							listener, t.getCause());
+				}
+                finally
+                {
+                	Thread.currentThread().setContextClassLoader(myClassLoader);
+                }
+            }
+        };
+
+        final long startNotify = System.currentTimeMillis();
+        try {
+            if (null != listener.getExecutor()) {
+                listener.getExecutor().execute(job);
+            } else {
+                job.run();
+            }
+        } catch (Throwable t) {
+			log.error(
+					name,
+					"NACOS-XXXX",
+					"[notify-error] dataId={}, group={}, md5={}, listener={} throwable={}",
+					dataId, group, md5, listener, t.getCause());
+        }
+        final long finishNotify = System.currentTimeMillis();
+        log.info(name, "[notify-listener] time cost={}ms in ClientWorker, dataId={}, group={}, md5={}, listener={} ",(finishNotify - startNotify), dataId ,group, md5, listener);
+    }
+    
+    static public String getMd5String(String config) {
+        return (null == config) ? Constants.NULL : MD5.getInstance().getMD5String(config);
+    }
+
+    private String loadCacheContentFromDiskLocal(String name, String dataId, String group, String tenant) {
+		String content = LocalConfigInfoProcessor.getFailover(name, dataId, group, tenant);
+		content = (null != content) ? content
+				: LocalConfigInfoProcessor.getSnapshot(name, dataId, group, tenant);
+		return content;
+    }
+    
+	public CacheData(ConfigFilterChainManager configFilterChainManager, String name, String dataId, String group) {
+		if (null == dataId || null == group) {
+			throw new IllegalArgumentException("dataId=" + dataId + ", group=" + group);
+		}
+		this.name = name;
+		this.configFilterChainManager = configFilterChainManager;
+		this.dataId = dataId;
+		this.group = group;
+		this.tenant = TenantUtil.getUserTenant();
+		listeners = new CopyOnWriteArrayList<ManagerListenerWrap>();
+		this.isInitializing = true;
+		this.content = loadCacheContentFromDiskLocal(name, dataId, group, tenant);
+		this.md5 = getMd5String(content);
+    }
+    
+    public CacheData(ConfigFilterChainManager configFilterChainManager, String name, String dataId, String group, String tenant) {
+    	if (null == dataId || null == group) {
+    		throw new IllegalArgumentException("dataId=" + dataId + ", group=" + group);
+    	}
+    	this.name = name;
+		this.configFilterChainManager = configFilterChainManager;
+    	this.dataId = dataId;
+    	this.group = group;
+    	this.tenant = tenant;
+    	listeners = new CopyOnWriteArrayList<ManagerListenerWrap>();
+    	this.isInitializing = true;
+    	this.content = loadCacheContentFromDiskLocal(name, dataId, group, tenant);
+    	this.md5 = getMd5String(content);
+    }
+    
+    // ==================
+
+    private final String name;
+    private final ConfigFilterChainManager configFilterChainManager;
+    public final String dataId;
+    public final String group;
+    public final String tenant;
+    private final CopyOnWriteArrayList<ManagerListenerWrap> listeners;
+
+	private volatile String md5;
+	/**
+	 * whether use local config
+	 */
+	private volatile boolean isUseLocalConfig = false;
+	/**
+	 * last motify time
+	 */
+	private volatile long localConfigLastModified;
+	private volatile String content;
+    private int taskId;
+    private volatile boolean isInitializing = true;
+}
+
+class ManagerListenerWrap {
+    final Listener listener;
+    String lastCallMd5 = CacheData.getMd5String(null);
+
+    ManagerListenerWrap(Listener listener) {
+        this.listener = listener;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (null == obj || obj.getClass() != getClass()) {
+            return false;
+        }
+        if (obj == this) {
+            return true;
+        }
+        ManagerListenerWrap other = (ManagerListenerWrap) obj;
+        return listener.equals(other.listener);
+    }
+
+	@Override
+	public int hashCode() {
+		return super.hashCode();
+	}
+
+}

client/src/main/java/com/alibaba/nacos/client/config/impl/ClientWorker.java

@@ -0,0 +1,541 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import static com.alibaba.nacos.client.config.common.Constants.LINE_SEPARATOR;
+import static com.alibaba.nacos.client.config.common.Constants.WORD_SEPARATOR;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URLDecoder;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
+
+import com.alibaba.nacos.api.config.listener.Listener;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.client.config.common.Constants;
+import com.alibaba.nacos.client.config.common.GroupKey;
+import com.alibaba.nacos.client.config.filter.impl.ConfigFilterChainManager;
+import com.alibaba.nacos.client.config.impl.HttpSimpleClient.HttpResult;
+import com.alibaba.nacos.client.config.utils.ContentUtils;
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.config.utils.MD5;
+import com.alibaba.nacos.client.config.utils.TenantUtil;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+import com.alibaba.nacos.client.utils.ParamUtil;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
+/**
+ * Longpulling
+ * 
+ * @author Nacos
+ *
+ */
+public class ClientWorker {
+	
+	final static public Logger log = LogUtils.logger(ClientWorker.class);
+
+	public void addListeners(String dataId, String group, List<? extends Listener> listeners) {
+        group = null2defaultGroup(group);
+        CacheData cache = addCacheDataIfAbsent(dataId, group);
+        for (Listener listener : listeners) {
+            cache.addListener(listener);
+        }
+	}
+	
+	public void removeListener(String dataId, String group, Listener listener) {
+		group = null2defaultGroup(group);
+        CacheData cache = getCache(dataId, group);
+        if (null != cache) {
+            cache.removeListener(listener);
+            if (cache.getListeners().isEmpty()) {
+                removeCache(dataId, group);
+            }
+        }
+	}
+	
+	public void addTenantListeners(String dataId, String group, List<? extends Listener> listeners) {
+		group = null2defaultGroup(group);
+		String tenant = agent.getTenant();
+		CacheData cache = addCacheDataIfAbsent(dataId, group, tenant);
+		for (Listener listener : listeners) {
+			cache.addListener(listener);
+		}
+	}
+	
+	public void removeTenantListener(String dataId, String group, Listener listener) {
+		group = null2defaultGroup(group);
+		String tenant = agent.getTenant();
+		CacheData cache = getCache(dataId, group, tenant);
+		if (null != cache) {
+			cache.removeListener(listener);
+			if (cache.getListeners().isEmpty()) {
+				removeCache(dataId, group, tenant);
+			}
+		}
+	}
+	
+	@SuppressFBWarnings("JLM_JSR166_UTILCONCURRENT_MONITORENTER")
+    void removeCache(String dataId, String group) {
+        String groupKey = GroupKey.getKey(dataId, group);
+        synchronized (cacheMap) {
+            Map<String, CacheData> copy = new HashMap<String, CacheData>(cacheMap.get());
+            copy.remove(groupKey);
+            cacheMap.set(copy);
+        }
+        log.info(agent.getName(), "[unsubscribe] {}", groupKey);
+    }
+	
+	@SuppressFBWarnings("JLM_JSR166_UTILCONCURRENT_MONITORENTER")
+    void removeCache(String dataId, String group, String tenant) {
+    	String groupKey = GroupKey.getKeyTenant(dataId, group, tenant);
+    	synchronized (cacheMap) {
+    		Map<String, CacheData> copy = new HashMap<String, CacheData>(cacheMap.get());
+    		copy.remove(groupKey);
+    		cacheMap.set(copy);
+    	}
+    	log.info(agent.getName(), "[unsubscribe] {}", groupKey);
+    }
+	
+	@SuppressFBWarnings("JLM_JSR166_UTILCONCURRENT_MONITORENTER")
+	public CacheData addCacheDataIfAbsent(String dataId, String group) {
+        CacheData cache = getCache(dataId, group);
+        if (null != cache) {
+            return cache;
+        }
+
+        String key = GroupKey.getKey(dataId, group);
+        cache = new CacheData(configFilterChainManager, agent.getName(), dataId, group);
+        
+        synchronized (cacheMap) {
+        	CacheData cacheFromMap = getCache(dataId, group);
+        	// multiple listeners on the same dataid+group and race condition,so double check again
+        	//other listener thread beat me to set to cacheMap
+        	if(null != cacheFromMap) {
+        		cache = cacheFromMap;
+        		//reset so that server not hang this check
+        		cache.setInitializing(true); 
+			} else {
+				int taskId = cacheMap.get().size() / (int) ParamUtil.getPerTaskConfigSize();
+				cache.setTaskId(taskId);
+			}
+        	
+            Map<String, CacheData> copy = new HashMap<String, CacheData>(cacheMap.get());
+            copy.put(key, cache);
+            cacheMap.set(copy);
+        }
+        
+        log.info(agent.getName(), "[subscribe] {}", key);
+        
+        return cache;
+    }
+	@SuppressFBWarnings("JLM_JSR166_UTILCONCURRENT_MONITORENTER")
+	public CacheData addCacheDataIfAbsent(String dataId, String group, String tenant) {
+		CacheData cache = getCache(dataId, group, tenant);
+		if (null != cache) {
+			return cache;
+		}
+		String key = GroupKey.getKeyTenant(dataId, group, tenant);
+		cache = new CacheData(configFilterChainManager, agent.getName(), dataId, group, tenant);
+		synchronized (cacheMap) {
+			CacheData cacheFromMap = getCache(dataId, group, tenant);
+			// multiple listeners on the same dataid+group and race condition,so
+			// double check again
+			// other listener thread beat me to set to cacheMap
+			if (null != cacheFromMap) {
+				cache = cacheFromMap;
+				// reset so that server not hang this check
+				cache.setInitializing(true);
+			}
+
+			Map<String, CacheData> copy = new HashMap<String, CacheData>(cacheMap.get());
+			copy.put(key, cache);
+			cacheMap.set(copy);
+		}
+		log.info(agent.getName(), "[subscribe] {}", key);
+		return cache;
+	}
+    
+	public CacheData getCache(String dataId, String group) {
+		return getCache(dataId, group, TenantUtil.getUserTenant());
+	}
+    
+	public CacheData getCache(String dataId, String group, String tenant) {
+		if (null == dataId || null == group) {
+			throw new IllegalArgumentException();
+		}
+		return cacheMap.get().get(GroupKey.getKeyTenant(dataId, group, tenant));
+	}
+    
+
+	public String getServerConfig(String dataId, String group, String tenant, long readTimeout)
+			throws NacosException {
+		if (StringUtils.isBlank(group)) {
+			group = Constants.DEFAULT_GROUP;
+		}
+
+		HttpResult result = null;
+		try {
+			List<String> params = null;
+			if (StringUtils.isBlank(tenant)) {
+				params = Arrays.asList("dataId", dataId, "group", group);
+			} else {
+				params = Arrays.asList("dataId", dataId, "group", group, "tenant", tenant);
+			}
+			result = agent.httpGet(Constants.CONFIG_CONTROLLER_PATH, null, params, agent.getEncode(), readTimeout);
+		} catch (IOException e) {
+			log.error(agent.getName(), "NACOS-XXXX",
+					"[sub-server] get server config exception, dataId={}, group={}, tenant={}, msg={}", dataId, group,
+					tenant, e.toString());
+			throw new NacosException(NacosException.SERVER_ERROR, e.getMessage());
+		}
+
+		switch (result.code) {
+		case HttpURLConnection.HTTP_OK:
+			LocalConfigInfoProcessor.saveSnapshot(agent.getName(), dataId, group, tenant, result.content);
+			return result.content;
+		case HttpURLConnection.HTTP_NOT_FOUND:
+			LocalConfigInfoProcessor.saveSnapshot(agent.getName(), dataId, group, tenant, null);
+			return null;
+		case HttpURLConnection.HTTP_CONFLICT: {
+			log.error(agent.getName(), "NACOS-XXXX",
+					"[sub-server-error] get server config being modified concurrently, dataId={}, group={}, tenant={}",
+					dataId, group, tenant);
+			throw new NacosException(NacosException.CONFLICT,
+					"data being modified, dataId=" + dataId + ",group=" + group + ",tenant=" + tenant);
+		}
+		case HttpURLConnection.HTTP_FORBIDDEN: {
+			log.error(agent.getName(), "NACOS-XXXX", "[sub-server-error] no right, dataId={}, group={}, tenant={}",
+					dataId, group, tenant);
+			throw new NacosException(result.code, result.content);
+		}
+		default: {
+			log.error(agent.getName(), "NACOS-XXXX", "[sub-server-error]  dataId={}, group={}, tenant={}, code={}",
+					dataId, group, tenant, result.code);
+			throw new NacosException(result.code,
+					"http error, code=" + result.code + ",dataId=" + dataId + ",group=" + group + ",tenant=" + tenant);
+		}
+		}
+	}
+
+	private void checkLocalConfig(CacheData cacheData) {
+		final String dataId = cacheData.dataId;
+		final String group = cacheData.group;
+		final String tenant = cacheData.tenant;
+		File path = LocalConfigInfoProcessor.getFailoverFile(agent.getName(), dataId, group, tenant);
+
+		// 没有 -> 有
+		if (!cacheData.isUseLocalConfigInfo() && path.exists()) {
+			String content = LocalConfigInfoProcessor.getFailover(agent.getName(), dataId, group, tenant);
+			String md5 = MD5.getInstance().getMD5String(content);
+			cacheData.setUseLocalConfigInfo(true);
+			cacheData.setLocalConfigInfoVersion(path.lastModified());
+			cacheData.setContent(content);
+
+			log.warn(agent.getName(),
+					"[failover-change] failover file created. dataId={}, group={}, tenant={}, md5={}, content={}",
+					dataId, group, tenant, md5, ContentUtils.truncateContent(content));
+			return;
+		}
+
+		// 有 -> 没有。不通知业务监听器，从server拿到配置后通知。
+		if (cacheData.isUseLocalConfigInfo() && !path.exists()) {
+			cacheData.setUseLocalConfigInfo(false);
+			log.warn(agent.getName(), "[failover-change] failover file deleted. dataId={}, group={}, tenant={}", dataId,
+					group, tenant);
+			return;
+		}
+
+		// 有变更
+		if (cacheData.isUseLocalConfigInfo() && path.exists()
+				&& cacheData.getLocalConfigInfoVersion() != path.lastModified()) {
+			String content = LocalConfigInfoProcessor.getFailover(agent.getName(), dataId, group, tenant);
+			String md5 = MD5.getInstance().getMD5String(content);
+			cacheData.setUseLocalConfigInfo(true);
+			cacheData.setLocalConfigInfoVersion(path.lastModified());
+			cacheData.setContent(content);
+			log.warn(agent.getName(),
+					"[failover-change] failover file changed. dataId={}, group={}, tenant={}, md5={}, content={}",
+					dataId, group, tenant, md5, ContentUtils.truncateContent(content));
+			return;
+		}
+	}
+	
+    private String null2defaultGroup(String group) {
+        return (null == group) ? Constants.DEFAULT_GROUP : group.trim();
+    }
+    
+	public void checkConfigInfo() {
+		// 分任务
+		int listenerSize = cacheMap.get().size();
+		// 向上取整为批数
+		int longingTaskCount = (int) Math.ceil(listenerSize / ParamUtil.getPerTaskConfigSize());
+		if (longingTaskCount > currentLongingTaskCount) {
+			for (int i = (int) currentLongingTaskCount; i < longingTaskCount; i++) {
+				// 要判断任务是否在执行 这块需要好好想想。 任务列表现在是无序的。变化过程可能有问题
+				executorService.execute(new LongPullingRunnable(i));
+			}
+			currentLongingTaskCount = longingTaskCount;
+		}
+	}
+
+	/**
+	 * 从Server获取值变化了的DataID列表。返回的对象里只有dataId和group是有效的。 保证不返回NULL。
+	 */
+	List<String> checkUpdateDataIds(List<CacheData> cacheDatas, List<String> inInitializingCacheList) {
+		StringBuilder sb = new StringBuilder();
+		for (CacheData cacheData : cacheDatas) {
+			if (!cacheData.isUseLocalConfigInfo()) {
+				sb.append(cacheData.dataId).append(WORD_SEPARATOR);
+				sb.append(cacheData.group).append(WORD_SEPARATOR);
+				if (StringUtils.isBlank(cacheData.tenant)) {
+					sb.append(cacheData.getMd5()).append(LINE_SEPARATOR);
+				} else {
+					sb.append(cacheData.getMd5()).append(WORD_SEPARATOR);
+					sb.append(cacheData.getTenant()).append(LINE_SEPARATOR);
+				}
+				if (cacheData.isInitializing()) {
+					// cacheData 首次出现在cacheMap中&首次check更新
+					inInitializingCacheList
+							.add(GroupKey.getKeyTenant(cacheData.dataId, cacheData.group, cacheData.tenant));
+				}
+			}
+		}
+		boolean isInitializingCacheList = !inInitializingCacheList.isEmpty();
+		return checkUpdateConfigStr(sb.toString(), isInitializingCacheList);
+	}
+
+	/**
+	 * 从Server获取值变化了的DataID列表。返回的对象里只有dataId和group是有效的。 保证不返回NULL。
+	 */
+	List<String> checkUpdateConfigStr(String probeUpdateString, boolean isInitializingCacheList) {
+
+		List<String> params = Arrays.asList(Constants.PROBE_MODIFY_REQUEST, probeUpdateString);
+		long timeout = TimeUnit.SECONDS.toMillis(30L);
+
+		List<String> headers = new ArrayList<String>(2);
+		headers.add("Long-Pulling-Timeout");
+		headers.add("" + timeout);
+
+		// told server do not hang me up if new initializing cacheData added in
+		if (isInitializingCacheList) {
+			headers.add("Long-Pulling-Timeout-No-Hangup");
+			headers.add("true");
+		}
+
+		if (StringUtils.isBlank(probeUpdateString)) {
+			return Collections.emptyList();
+		}
+
+		try {
+			HttpResult result = agent.httpPost(Constants.CONFIG_CONTROLLER_PATH + "/listener", headers, params,
+					agent.getEncode(), timeout);
+
+			if (HttpURLConnection.HTTP_OK == result.code) {
+				setHealthServer(true);
+				return parseUpdateDataIdResponse(result.content);
+			} else {
+				setHealthServer(false);
+				if (result.code == HttpURLConnection.HTTP_INTERNAL_ERROR) {
+					log.error("NACOS-0007", LoggerHelper.getErrorCodeStr("Nacos", "Nacos-0007", "环境问题",
+							"[check-update] get changed dataId error"));
+				}
+				log.error(agent.getName(), "NACOS-XXXX", "[check-update] get changed dataId error, code={}",
+						result.code);
+			}
+		} catch (IOException e) {
+			setHealthServer(false);
+			log.error(agent.getName(), "NACOS-XXXX", "[check-update] get changed dataId exception, msg={}",
+					e.toString());
+		}
+		return Collections.emptyList();
+	}
+
+	/**
+	 * 从HTTP响应拿到变化的groupKey。保证不返回NULL。
+	 */
+	private List<String> parseUpdateDataIdResponse(String response) {
+		if (StringUtils.isBlank(response)) {
+			return Collections.emptyList();
+		}
+
+		try {
+			response = URLDecoder.decode(response, "UTF-8");
+		} catch (Exception e) {
+			log.error(agent.getName(), "NACOS-XXXX", "[polling-resp] decode modifiedDataIdsString error", e);
+		}
+
+		List<String> updateList = new LinkedList<String>();
+
+		for (String dataIdAndGroup : response.split(LINE_SEPARATOR)) {
+			if (!StringUtils.isBlank(dataIdAndGroup)) {
+				String[] keyArr = dataIdAndGroup.split(WORD_SEPARATOR);
+				String dataId = keyArr[0];
+				String group = keyArr[1];
+				if (keyArr.length == 2) {
+					updateList.add(GroupKey.getKey(dataId, group));
+					log.info(agent.getName(), "[polling-resp] config changed. dataId={}, group={}", dataId, group);
+				} else if (keyArr.length == 3) {
+					String tenant = keyArr[2];
+					updateList.add(GroupKey.getKeyTenant(dataId, group, tenant));
+					log.info(agent.getName(), "[polling-resp] config changed. dataId={}, group={}, tenant={}", dataId,
+							group, tenant);
+				} else {
+					log.error(agent.getName(), "NACOS-XXXX", "[polling-resp] invalid dataIdAndGroup error",
+							dataIdAndGroup);
+				}
+			}
+		}
+		return updateList;
+	}
+
+	@SuppressWarnings("PMD.ThreadPoolCreationRule")
+	public ClientWorker(final ServerHttpAgent agent, final ConfigFilterChainManager configFilterChainManager) {
+		this.agent = agent;
+		this.configFilterChainManager = configFilterChainManager;
+		executor = Executors.newScheduledThreadPool(1, new ThreadFactory() {
+			@Override
+			public Thread newThread(Runnable r) {
+				Thread t = new Thread(r);
+				t.setName("com.alibaba.nacos.client.Worker." + agent.getName());
+				t.setDaemon(true);
+				return t;
+			}
+		});
+
+		executorService = Executors.newCachedThreadPool(new ThreadFactory() {
+			@Override
+			public Thread newThread(Runnable r) {
+				Thread t = new Thread(r);
+				t.setName("com.alibaba.nacos.client.Worker.longPulling" + agent.getName());
+				t.setDaemon(true);
+				return t;
+			}
+		});
+
+		executor.scheduleWithFixedDelay(new Runnable() {
+			public void run() {
+				try {
+					checkConfigInfo();
+				} catch (Throwable e) {
+					log.error(agent.getName(), "NACOS-XXXX", "[sub-check] rotate check error", e);
+				}
+			}
+		}, 1L, 10L, TimeUnit.MILLISECONDS);
+	}
+
+	class LongPullingRunnable implements Runnable {
+		private int taskId;
+
+		public LongPullingRunnable(int taskId) {
+			this.taskId = taskId;
+		}
+
+		public void run() {
+			try {
+				List<CacheData> cacheDatas = new ArrayList<CacheData>();
+				// check failover config
+				for (CacheData cacheData : cacheMap.get().values()) {
+					if (cacheData.getTaskId() == taskId) {
+						cacheDatas.add(cacheData);
+						try {
+							checkLocalConfig(cacheData);
+							if (cacheData.isUseLocalConfigInfo()) {
+								cacheData.checkListenerMd5();
+							}
+						} catch (Exception e) {
+							log.error("NACOS-CLIENT", "get local config info error", e);
+						}
+					}
+				}
+
+				List<String> inInitializingCacheList = new ArrayList<String>();
+				// check server config
+				List<String> changedGroupKeys = checkUpdateDataIds(cacheDatas, inInitializingCacheList);
+
+				for (String groupKey : changedGroupKeys) {
+					String[] key = GroupKey.parseKey(groupKey);
+					String dataId = key[0];
+					String group = key[1];
+					String tenant = null;
+					if (key.length == 3) {
+						tenant = key[2];
+					}
+					try {
+						String content = getServerConfig(dataId, group, tenant, 3000L);
+						CacheData cache = cacheMap.get().get(GroupKey.getKeyTenant(dataId, group, tenant));
+						cache.setContent(content);
+						log.info(agent.getName(), "[data-received] dataId={}, group={}, tenant={}, md5={}, content={}",
+								dataId, group, tenant, cache.getMd5(), ContentUtils.truncateContent(content));
+					} catch (NacosException ioe) {
+						log.error(agent.getName(), "NACOS-XXXX",
+								"[get-update] get changed config exception. dataId={}, group={}, tenant={}, msg={}",
+								dataId, group, tenant, ioe.toString());
+					}
+				}
+				for (CacheData cacheData : cacheDatas) {
+					if (!cacheData.isInitializing() || inInitializingCacheList
+							.contains(GroupKey.getKeyTenant(cacheData.dataId, cacheData.group, cacheData.tenant))) {
+						cacheData.checkListenerMd5();
+						cacheData.setInitializing(false);
+					}
+				}
+				inInitializingCacheList.clear();
+			} catch (Throwable e) {
+				log.error("500", "longPulling error", e);
+			} finally {
+				executorService.execute(this);
+			}
+		}
+	}
+
+	// =================
+
+	public boolean isHealthServer() {
+		return isHealthServer;
+	}
+
+	private void setHealthServer(boolean isHealthServer) {
+		this.isHealthServer = isHealthServer;
+	}
+
+	final ScheduledExecutorService executor;
+	final ExecutorService executorService;
+	/**
+	 * groupKey -> cacheData
+	 */
+	AtomicReference<Map<String, CacheData>> cacheMap = new AtomicReference<Map<String, CacheData>>(new HashMap<String, CacheData>());
+	ServerHttpAgent agent;
+	ConfigFilterChainManager configFilterChainManager;
+	private boolean isHealthServer = true;
+	private double currentLongingTaskCount = 0;
+	
+}

client/src/main/java/com/alibaba/nacos/client/config/impl/EventDispatcher.java

@@ -0,0 +1,133 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.logger.Logger;
+
+
+/**
+ * Event subscription and publishing tools.
+ * 
+ * @author Nacos
+ *
+ */
+public class EventDispatcher {
+	
+	final static public Logger log = LogUtils.logger(EventDispatcher.class);
+
+    /**
+     * 添加事件监听器
+     */
+    static public void addEventListener(AbstractEventListener listener) {
+        for (Class<? extends AbstractEvent> type : listener.interest()) {
+            getListenerList(type).addIfAbsent(listener);
+        }
+    }
+
+    /**
+     * 发布事件，首先发布该事件暗示的其他事件，最后通知所有对应的监听器。
+     */
+    static public void fireEvent(AbstractEvent abstractEvent) {
+        if (null == abstractEvent) {
+            return;
+        }
+
+        // 发布该事件暗示的其他事件
+        for (AbstractEvent implyEvent : abstractEvent.implyEvents()) {
+            try {
+            	// 避免死循环
+                if (abstractEvent != implyEvent) {
+                    fireEvent(implyEvent);
+                }
+            } catch (Exception e) {
+                log.warn("", e.toString(), e);
+            }
+        }
+
+        for (AbstractEventListener listener : getListenerList(abstractEvent.getClass())) {
+            try {
+                listener.onEvent(abstractEvent);
+            } catch (Exception e) {
+                log.warn(e.toString(), e);
+            }
+        }
+    }
+
+    static synchronized CopyOnWriteArrayList<AbstractEventListener> getListenerList(
+            Class<? extends AbstractEvent> eventType) {
+        CopyOnWriteArrayList<AbstractEventListener> listeners = LISTENER_MAP.get(eventType);
+        if (null == listeners) {
+            listeners = new CopyOnWriteArrayList<AbstractEventListener>();
+            LISTENER_MAP.put(eventType, listeners);
+        }
+        return listeners;
+    }
+
+    // ========================
+    
+	static final Map<Class<? extends AbstractEvent>, CopyOnWriteArrayList<AbstractEventListener>> LISTENER_MAP = new HashMap<Class<? extends AbstractEvent>, CopyOnWriteArrayList<AbstractEventListener>>();
+
+    // ========================
+
+    /**
+     * Client事件。
+     */
+    static public abstract class AbstractEvent {
+
+        @SuppressWarnings("unchecked")
+        protected List<AbstractEvent> implyEvents() {
+            return Collections.EMPTY_LIST;
+        }
+    }
+
+    /**
+     * 事件监听器。
+     */
+    static public abstract class AbstractEventListener {
+        public AbstractEventListener() {
+			/**
+			 * 自动注册给EventDispatcher
+			 */
+            EventDispatcher.addEventListener(this); 
+        }
+        
+		/**
+		 * 感兴趣的事件列表
+		 * 
+		 * @return event list
+		 */
+        abstract public List<Class<? extends AbstractEvent>> interest();
+
+        /**
+         * 处理事件
+         * @param abstractEvent event to do
+         */
+        abstract public void onEvent(AbstractEvent abstractEvent);
+    }
+
+	/**
+	 * serverList has changed
+	 */
+	static public class ServerlistChangeEvent extends AbstractEvent {
+	}
+}

client/src/main/java/com/alibaba/nacos/client/config/impl/HttpSimpleClient.java

@@ -0,0 +1,276 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import java.io.IOException;
+import java.io.UnsupportedEncodingException;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.net.URLEncoder;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.client.config.common.Constants;
+import com.alibaba.nacos.client.config.utils.IOUtils;
+import com.alibaba.nacos.client.config.utils.MD5;
+import com.alibaba.nacos.client.utils.EnvUtil;
+import com.alibaba.nacos.client.utils.ParamUtil;
+import com.alibaba.nacos.common.util.UuidUtil;
+
+/**
+ * Http tool
+ * 
+ * @author Nacos
+ *
+ */
+public class HttpSimpleClient {
+
+
+    static public HttpResult httpGet(String url, List<String> headers, List<String> paramValues,
+            String encoding, long readTimeoutMs, boolean isSSL) throws IOException{
+    	String encodedContent = encodingParams(paramValues, encoding);
+        url += (null == encodedContent) ? "" : ("?" + encodedContent);
+		if (Limiter.isLimit(MD5.getInstance().getMD5String(
+				new StringBuilder(url).append(encodedContent).toString()))) {
+			return new HttpResult(NacosException.CLIENT_OVER_THRESHOLD,
+					"More than client-side current limit threshold");
+		}
+        
+        HttpURLConnection conn = null;
+        
+		try {
+			conn = (HttpURLConnection) new URL(url).openConnection();
+			conn.setRequestMethod("GET");
+			conn.setConnectTimeout(ParamUtil.getConnectTimeout() > 100 ? ParamUtil.getConnectTimeout() : 100);
+			conn.setReadTimeout((int) readTimeoutMs);
+			List<String> newHeaders = getHeaders(url, headers, paramValues);
+			setHeaders(conn, newHeaders, encoding);
+
+			conn.connect();
+			
+			int respCode = conn.getResponseCode();
+			String resp = null;
+
+			if (HttpURLConnection.HTTP_OK == respCode) {
+				resp = IOUtils.toString(conn.getInputStream(), encoding);
+			} else {
+				resp = IOUtils.toString(conn.getErrorStream(), encoding);
+			}
+			return new HttpResult(respCode, conn.getHeaderFields(), resp);
+		} finally {
+            if (conn != null) {
+                conn.disconnect();
+            }
+        }
+    }
+
+
+	/**
+	 * 发送GET请求。
+	 */
+	static public HttpResult httpGet(String url, List<String> headers, List<String> paramValues, String encoding,
+			long readTimeoutMs) throws IOException {
+		return httpGet(url, headers, paramValues, encoding, readTimeoutMs, false);
+	}
+
+    /**
+     * 发送POST请求。
+     * 
+     * @param url
+     * @param headers
+     *            请求Header，可以为null
+     * @param paramValues
+     *            参数，可以为null
+     * @param encoding
+     *            URL编码使用的字符集
+     * @param readTimeoutMs
+     *            响应超时
+     * @param isSSL
+     *            是否https
+     * @return
+     * @throws IOException
+     */
+    static public HttpResult httpPost(String url, List<String> headers, List<String> paramValues,
+            String encoding, long readTimeoutMs, boolean isSSL) throws IOException {
+		String encodedContent = encodingParams(paramValues, encoding);
+		if (Limiter.isLimit(MD5.getInstance().getMD5String(
+				new StringBuilder(url).append(encodedContent).toString()))) {
+			return new HttpResult(NacosException.CLIENT_OVER_THRESHOLD,
+					"More than client-side current limit threshold");
+		}
+        HttpURLConnection conn = null;
+        try {
+			conn = (HttpURLConnection) new URL(url).openConnection();
+            conn.setRequestMethod("POST");
+            conn.setConnectTimeout(ParamUtil.getConnectTimeout() > 3000 ? ParamUtil.getConnectTimeout() : 3000);
+            conn.setReadTimeout((int) readTimeoutMs);
+            conn.setDoOutput(true);
+            conn.setDoInput(true);
+			List<String> newHeaders = getHeaders(url, headers, paramValues);
+			setHeaders(conn, newHeaders, encoding);
+
+            conn.getOutputStream().write(encodedContent.getBytes(encoding));
+
+            int respCode = conn.getResponseCode();
+            String resp = null;
+
+            if (HttpURLConnection.HTTP_OK == respCode) {
+                resp = IOUtils.toString(conn.getInputStream(), encoding);
+            } else {
+                resp = IOUtils.toString(conn.getErrorStream(), encoding);
+            }
+            return new HttpResult(respCode, conn.getHeaderFields(), resp);
+        } finally {
+            if (null != conn) {
+                conn.disconnect();
+            }
+        }
+    }
+    
+	/**
+	 * 发送POST请求。
+	 * 
+	 * @param url
+	 * @param headers
+	 *            请求Header，可以为null
+	 * @param paramValues
+	 *            参数，可以为null
+	 * @param encoding
+	 *            URL编码使用的字符集
+	 * @param readTimeoutMs
+	 *            响应超时
+	 * @return
+	 * @throws IOException
+	 */
+	static public HttpResult httpPost(String url, List<String> headers, List<String> paramValues, String encoding,
+			long readTimeoutMs) throws IOException {
+		return httpPost(url, headers, paramValues, encoding, readTimeoutMs, false);
+	}
+
+	
+    static public HttpResult httpDelete(String url, List<String> headers, List<String> paramValues,
+            String encoding, long readTimeoutMs, boolean isSSL) throws IOException{
+    	String encodedContent = encodingParams(paramValues, encoding);
+        url += (null == encodedContent) ? "" : ("?" + encodedContent);
+		if (Limiter.isLimit(MD5.getInstance().getMD5String(
+				new StringBuilder(url).append(encodedContent).toString()))) {
+			return new HttpResult(NacosException.CLIENT_OVER_THRESHOLD,
+					"More than client-side current limit threshold");
+		}
+        
+        HttpURLConnection conn = null;
+        
+		try {
+			conn = (HttpURLConnection) new URL(url).openConnection();
+			conn.setRequestMethod("DELETE");
+			conn.setConnectTimeout(ParamUtil.getConnectTimeout() > 100 ? ParamUtil.getConnectTimeout() : 100);
+			conn.setReadTimeout((int) readTimeoutMs);
+			List<String> newHeaders = getHeaders(url, headers, paramValues);
+			setHeaders(conn, newHeaders, encoding);
+
+			conn.connect();
+			
+			int respCode = conn.getResponseCode();
+			String resp = null;
+
+			if (HttpURLConnection.HTTP_OK == respCode) {
+				resp = IOUtils.toString(conn.getInputStream(), encoding);
+			} else {
+				resp = IOUtils.toString(conn.getErrorStream(), encoding);
+			}
+			return new HttpResult(respCode, conn.getHeaderFields(), resp);
+		} finally {
+            if (conn != null) {
+                conn.disconnect();
+            }
+        }
+    }
+
+
+	static public HttpResult httpDelete(String url, List<String> headers, List<String> paramValues, String encoding,
+			long readTimeoutMs) throws IOException {
+		return httpGet(url, headers, paramValues, encoding, readTimeoutMs, false);
+	}
+	
+    static private void setHeaders(HttpURLConnection conn, List<String> headers, String encoding) {
+        if (null != headers) {
+            for (Iterator<String> iter = headers.iterator(); iter.hasNext();) {
+                conn.addRequestProperty(iter.next(), iter.next());
+            }
+        }
+        conn.addRequestProperty("Client-Version", ParamUtil.getClientVersion());
+        conn.addRequestProperty("Content-Type", "application/x-www-form-urlencoded;charset=" + encoding);
+        
+        String ts = String.valueOf(System.currentTimeMillis());
+        String token = MD5.getInstance().getMD5String(ts + ParamUtil.getAppKey());
+
+        conn.addRequestProperty(Constants.CLIENT_APPNAME_HEADER, ParamUtil.getAppName());
+        conn.addRequestProperty(Constants.CLIENT_REQUEST_TS_HEADER, ts);
+        conn.addRequestProperty(Constants.CLIENT_REQUEST_TOKEN_HEADER, token);
+    }
+
+	private static List<String> getHeaders(String url, List<String> headers, List<String> paramValues)
+			throws IOException {
+		List<String> newHeaders = new ArrayList<String>();
+		newHeaders.add("exConfigInfo");
+		newHeaders.add("true");
+		newHeaders.add("RequestId");
+		newHeaders.add(UuidUtil.generateUuid());
+		if (headers!=null) {
+			newHeaders.addAll(headers);
+		}
+		return newHeaders;
+	}
+	
+    static private String encodingParams(List<String> paramValues, String encoding)
+            throws UnsupportedEncodingException {
+        StringBuilder sb = new StringBuilder();
+        if (null == paramValues) {
+            return null;
+        }
+        
+        for (Iterator<String> iter = paramValues.iterator(); iter.hasNext();) {
+            sb.append(iter.next()).append("=");
+            sb.append(URLEncoder.encode(iter.next(), encoding));
+            if (iter.hasNext()) {
+                sb.append("&");
+            }
+        }
+        return sb.toString();
+    }
+    
+    static public class HttpResult {
+        final public int code;
+        final public Map<String,List<String>> headers;
+        final public String content;
+
+		public HttpResult(int code, String content) {
+			this.code = code;
+			this.headers = null;
+			this.content = content;
+		}
+		
+		public HttpResult(int code, Map<String, List<String>> headers, String content) {
+			this.code = code;
+			this.headers = headers;
+			this.content = content;
+		}
+    }
+    
+}

client/src/main/java/com/alibaba/nacos/client/config/impl/Limiter.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.logger.Logger;
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
+import com.google.common.util.concurrent.RateLimiter;
+
+/**
+ * Limiter
+ * 
+ * @author Nacos
+ *
+ */
+public class Limiter {
+
+	static final public Logger log = LogUtils.logger(Limiter.class);
+	private static int CAPACITY_SIZE = 1000;
+	private static int LIMIT_TIME = 1000;
+	private static Cache<String, RateLimiter> cache = CacheBuilder.newBuilder()
+			.initialCapacity(CAPACITY_SIZE).expireAfterAccess(1, TimeUnit.MINUTES)
+			.build();
+
+	/**
+	 * qps 5
+	 */
+	private static final String DEFAULT_LIMIT = "5";
+	private static double limit = 5;
+
+	static {
+		try {
+			String limitTimeStr = System
+					.getProperty("limitTime", DEFAULT_LIMIT);
+			limit = Double.parseDouble(limitTimeStr);
+			log.info("limitTime:{}", limit);
+		} catch (Exception e) {
+			log.error("Nacos-xxx", "init limitTime fail", e);
+		}
+	}
+
+	public static boolean isLimit(String accessKeyID) {
+		RateLimiter rateLimiter = null;
+		try {
+			rateLimiter = cache.get(accessKeyID, new Callable<RateLimiter>() {
+				@Override
+				public RateLimiter call() throws Exception {
+					return RateLimiter.create(limit);
+				}
+			});
+		} catch (ExecutionException e) {
+			log.error("Nacos-XXX", "create limit fail", e);
+		}
+		if (rateLimiter != null && !rateLimiter.tryAcquire(LIMIT_TIME, TimeUnit.MILLISECONDS)) {
+			log.error("Nacos-XXX", "access_key_id:{} limited", accessKeyID);
+			return true;
+		}
+		return false;
+	}
+
+}

client/src/main/java/com/alibaba/nacos/client/config/impl/LocalConfigInfoProcessor.java

@@ -0,0 +1,197 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+import com.alibaba.nacos.client.config.common.Constants;
+import com.alibaba.nacos.client.config.utils.ConcurrentDiskUtil;
+import com.alibaba.nacos.client.config.utils.IOUtils;
+import com.alibaba.nacos.client.config.utils.JVMUtil;
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.config.utils.SnapShotSwitch;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+
+/**
+ * Local Disaster Recovery Directory Tool
+ * 
+ * @author Nacos
+ */
+public class LocalConfigInfoProcessor {
+	
+	final static public Logger log = LogUtils.logger(LocalConfigInfoProcessor.class);
+
+    static public String getFailover(String serverName, String dataId, String group, String tenant) {
+    	File localPath = getFailoverFile(serverName, dataId, group, tenant);
+    	if (!localPath.exists() || !localPath.isFile()) {
+    		return null;
+    	}
+    	
+    	try {
+    		return readFile(localPath);
+    	} catch (IOException ioe) {
+    		log.error(serverName, "NACOS-XXXX","get failover error, " + localPath + ioe.toString());
+    		return null;
+    	}
+    }
+    
+    /**
+     * 获取本地缓存文件内容。NULL表示没有本地文件或抛出异常。
+     */
+    static public String getSnapshot(String name, String dataId, String group, String tenant) {
+    	if (!SnapShotSwitch.getIsSnapShot()) {
+    		return null;
+    	}
+    	File file = getSnapshotFile(name, dataId, group, tenant);
+    	if (!file.exists() || !file.isFile()) {
+    		return null;
+    	}
+    	
+    	try {
+    		return readFile(file);
+    	} catch (IOException ioe) {
+    		log.error(name, "NACOS-XXXX","get snapshot error, " + file + ", " + ioe.toString());
+    		return null;
+    	}
+    }
+    
+	static private String readFile(File file) throws IOException {
+		if (!file.exists() || !file.isFile()) {
+			return null;
+		}
+
+		if (JVMUtil.isMultiInstance()) {
+			return ConcurrentDiskUtil.getFileContent(file, Constants.ENCODE);
+		} else {
+			InputStream is = null;
+			try {
+				is = new FileInputStream(file);
+				return IOUtils.toString(is, Constants.ENCODE);
+			} finally {
+				try {
+					if (null != is) {
+						is.close();
+					}
+				} catch (IOException ioe) {
+				}
+			}
+		}
+	}
+
+    
+    static public void saveSnapshot(String envName, String dataId, String group, String tenant, String config) {
+		if (!SnapShotSwitch.getIsSnapShot()) {
+			return;
+		}
+        File file = getSnapshotFile(envName, dataId, group, tenant);
+        if (null == config) {
+            try {
+                IOUtils.delete(file);
+            } catch (IOException ioe) {
+                log.error(envName, "NACOS-XXXX","delete snapshot error, " + file + ", " + ioe.toString());
+            }
+        } else {
+            try {
+				boolean isMdOk = file.getParentFile().mkdirs();
+				if (!isMdOk) {
+					log.error(envName, "NACOS-XXXX", "save snapshot error");
+				}
+				if (JVMUtil.isMultiInstance()) {
+					ConcurrentDiskUtil.writeFileContent(file, config,
+							Constants.ENCODE);
+				} else {
+					IOUtils.writeStringToFile(file, config, Constants.ENCODE);
+				}
+            } catch (IOException ioe) {
+                log.error(envName, "NACOS-XXXX","save snapshot error, " + file + ", " + ioe.toString());
+            }
+        }
+    }
+    
+    /**
+     * 清除snapshot目录下所有缓存文件。
+     */
+    static public void cleanAllSnapshot() {
+        try {
+        	File rootFile = new File(LOCAL_SNAPSHOT_PATH);
+        	File[] files = rootFile.listFiles();
+			if (files == null || files.length == 0) {
+				return;
+			}
+        	for(File file : files){
+        		if(file.getName().endsWith("_nacos")){
+        			IOUtils.cleanDirectory(file);
+        		}
+        	}
+        } catch (IOException ioe) {
+            log.error("NACOS-XXXX","clean all snapshot error, " + ioe.toString(), ioe);
+        }
+    }
+    
+    static public void cleanEnvSnapshot(String envName){
+    	File tmp = new File(LOCAL_SNAPSHOT_PATH, envName + "_nacos");
+    	tmp = new File(tmp, "snapshot");
+    	try {
+			IOUtils.cleanDirectory(tmp);
+			log.info("success dlelet " + envName + "-snapshot");
+		} catch (IOException e) {
+			log.info("fail dlelet " + envName + "-snapshot, " + e.toString());
+			e.printStackTrace();
+		}
+    }
+    
+
+    static File getFailoverFile(String serverName, String dataId, String group, String tenant) {
+    	File tmp = new File(LOCAL_SNAPSHOT_PATH, serverName + "_nacos");
+    	tmp = new File(tmp, "data");
+    	if (StringUtils.isBlank(tenant)) {
+    		tmp = new File(tmp, "config-data");
+    	} else
+    	{
+    		tmp = new File(tmp, "config-data-tenant");
+    		tmp = new File(tmp, tenant);
+    	}
+    	return new File(new File(tmp, group), dataId);
+    }
+    
+    static File getSnapshotFile(String envName, String dataId, String group, String tenant) {
+		File tmp = new File(LOCAL_SNAPSHOT_PATH, envName + "_nacos");
+		if (StringUtils.isBlank(tenant)) {
+			tmp = new File(tmp, "snapshot");
+		} else {
+			tmp = new File(tmp, "snapshot-tenant");
+			tmp = new File(tmp, tenant);
+		}
+    	
+        return new File(new File(tmp, group), dataId);
+    }
+    
+    public static final String LOCAL_FILEROOT_PATH;
+    public static final String LOCAL_SNAPSHOT_PATH;
+	static {
+		LOCAL_FILEROOT_PATH = System.getProperty("JM.LOG.PATH", System.getProperty("user.home")) + File.separator
+				+ "nacos" + File.separator + "config";
+		LOCAL_SNAPSHOT_PATH = System.getProperty("JM.SNAPSHOT.PATH", System.getProperty("user.home")) + File.separator
+				+ "nacos" + File.separator + "config";
+		log.warn("LOCAL_SNAPSHOT_PATH:{}", LOCAL_SNAPSHOT_PATH);
+	}
+
+}

client/src/main/java/com/alibaba/nacos/client/config/impl/ServerHttpAgent.java

@@ -0,0 +1,392 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import java.io.IOException;
+import java.net.ConnectException;
+import java.net.HttpURLConnection;
+import java.net.SocketTimeoutException;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+import java.util.Properties;
+
+import org.codehaus.jackson.annotate.JsonProperty;
+import org.codehaus.jackson.type.TypeReference;
+
+import com.alibaba.nacos.api.PropertyKeyConst;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.client.config.common.Constants;
+import com.alibaba.nacos.client.config.impl.HttpSimpleClient.HttpResult;
+import com.alibaba.nacos.client.config.utils.IOUtils;
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.identify.STSConfig;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+import com.alibaba.nacos.client.utils.JSONUtils;
+import com.alibaba.nacos.client.utils.ParamUtil;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+/**
+ * Server Agent 
+ * 
+ * @author water.lyl
+ *
+ */
+public class ServerHttpAgent {
+
+	final static public Logger log = LogUtils.logger(ServerHttpAgent.class);
+	/**
+	 * @param path
+	 *            相对于web应用根，以/开头
+	 * @param headers
+	 * @param paramValues
+	 * @param encoding
+	 * @param readTimeoutMs
+	 * @return
+	 * @throws IOException
+	 */
+	public HttpResult httpGet(String path, List<String> headers, List<String> paramValues, String encoding,
+			long readTimeoutMs) throws IOException {
+		final long endTime = System.currentTimeMillis() + readTimeoutMs;
+
+		boolean isSSL = false;
+		
+		do {
+			try {
+				List<String> newHeaders = getSpasHeaders(paramValues);
+				if (headers != null) {
+					newHeaders.addAll(headers);
+				}
+				HttpResult result = HttpSimpleClient.httpGet(
+						getUrl(serverListMgr.getCurrentServerAddr(), path, isSSL), newHeaders, paramValues, encoding,
+						readTimeoutMs, isSSL);
+				if (result.code == HttpURLConnection.HTTP_INTERNAL_ERROR
+						|| result.code == HttpURLConnection.HTTP_BAD_GATEWAY
+						|| result.code == HttpURLConnection.HTTP_UNAVAILABLE) {
+					log.error("NACOS ConnectException", "currentServerAddr:{}. httpCode:",
+							new Object[] { serverListMgr.getCurrentServerAddr(), result.code });
+				} else {
+					return result;
+				}
+			} catch (ConnectException ce) {
+				log.error("NACOS ConnectException", "currentServerAddr:{}",
+						new Object[] { serverListMgr.getCurrentServerAddr() });
+				serverListMgr.refreshCurrentServerAddr();
+			} catch (SocketTimeoutException stoe) {
+				log.error("NACOS  SocketTimeoutException", "currentServerAddr:{}",
+						new Object[] { serverListMgr.getCurrentServerAddr()});
+				serverListMgr.refreshCurrentServerAddr();
+			} catch (IOException ioe) {
+				log.error("NACOS  IOException", "currentServerAddr:{}",
+						new Object[] { serverListMgr.getCurrentServerAddr()});
+				throw ioe;
+			}
+		} while (System.currentTimeMillis() > endTime);
+
+		log.error("NACOS-0002",
+				LoggerHelper.getErrorCodeStr("NACOS", "NACOS-0002", "环境问题", "no available server"));
+		throw new ConnectException("no available server");
+	}
+
+	public HttpResult httpPost(String path, List<String> headers, List<String> paramValues, String encoding,
+			long readTimeoutMs) throws IOException {
+		final long endTime = System.currentTimeMillis() + readTimeoutMs;
+		boolean isSSL = false;
+		do {
+			try {
+				List<String> newHeaders = getSpasHeaders(paramValues);
+				if (headers != null) {
+					newHeaders.addAll(headers);
+				}
+				HttpResult result = HttpSimpleClient.httpPost(
+						getUrl(serverListMgr.getCurrentServerAddr(), path, isSSL), newHeaders, paramValues, encoding,
+						readTimeoutMs, isSSL);
+				if (result.code == HttpURLConnection.HTTP_INTERNAL_ERROR
+						|| result.code == HttpURLConnection.HTTP_BAD_GATEWAY
+						|| result.code == HttpURLConnection.HTTP_UNAVAILABLE) {
+					log.error("NACOS ConnectException", "currentServerAddr:{}. httpCode:",
+							new Object[] { serverListMgr.getCurrentServerAddr(), result.code });
+				} else {
+					return result;
+				}
+			} catch (ConnectException ce) {
+				log.error("NACOS ConnectException", "currentServerAddr:{}",
+						new Object[] { serverListMgr.getCurrentServerAddr()});
+				serverListMgr.refreshCurrentServerAddr();
+			} catch (SocketTimeoutException stoe) {
+				log.error("NACOS  SocketTimeoutException", "currentServerAddr:{}",
+						new Object[] { serverListMgr.getCurrentServerAddr()});
+				serverListMgr.refreshCurrentServerAddr();
+			} catch (IOException ioe) {
+				log.error("NACOS  IOException", "currentServerAddr:{}",
+						new Object[] { serverListMgr.getCurrentServerAddr()});
+				throw ioe;
+			}
+
+		} while (System.currentTimeMillis() > endTime);
+
+		log.error("NACOS-0002",
+				LoggerHelper.getErrorCodeStr("NACOS", "NACOS-0002", "环境问题", "no available server"));
+		throw new ConnectException("no available server");
+	}
+	
+	public HttpResult httpDelete(String path, List<String> headers, List<String> paramValues, String encoding,
+			long readTimeoutMs) throws IOException {
+		final long endTime = System.currentTimeMillis() + readTimeoutMs;
+		boolean isSSL = false;
+		do {
+			try {
+				List<String> newHeaders = getSpasHeaders(paramValues);
+				if (headers != null) {
+					newHeaders.addAll(headers);
+				}
+				HttpResult result = HttpSimpleClient.httpDelete(
+						getUrl(serverListMgr.getCurrentServerAddr(), path, isSSL), newHeaders, paramValues, encoding,
+						readTimeoutMs, isSSL);
+				if (result.code == HttpURLConnection.HTTP_INTERNAL_ERROR
+						|| result.code == HttpURLConnection.HTTP_BAD_GATEWAY
+						|| result.code == HttpURLConnection.HTTP_UNAVAILABLE) {
+					log.error("NACOS ConnectException", "currentServerAddr:{}. httpCode:",
+							new Object[] { serverListMgr.getCurrentServerAddr(), result.code });
+				} else {
+					return result;
+				}
+			} catch (ConnectException ce) {
+				log.error("NACOS ConnectException", "currentServerAddr:{}",
+						new Object[] { serverListMgr.getCurrentServerAddr()});
+				serverListMgr.refreshCurrentServerAddr();
+			} catch (SocketTimeoutException stoe) {
+				log.error("NACOS  SocketTimeoutException", "currentServerAddr:{}",
+						new Object[] { serverListMgr.getCurrentServerAddr()});
+				serverListMgr.refreshCurrentServerAddr();
+			} catch (IOException ioe) {
+				log.error("NACOS  IOException", "currentServerAddr:{}",
+						new Object[] { serverListMgr.getCurrentServerAddr()});
+				throw ioe;
+			}
+			
+		} while (System.currentTimeMillis() > endTime);
+		
+		log.error("NACOS-0002",
+				LoggerHelper.getErrorCodeStr("NACOS", "NACOS-0002", "环境问题", "no available server"));
+		throw new ConnectException("no available server");
+	}
+
+	private String getUrl(String serverAddr, String relativePath, boolean isSSL) {
+		String httpPrefix = "http://";
+		if (isSSL) {
+			httpPrefix = "https://";
+		}
+		return httpPrefix + serverAddr + "/" + serverListMgr.getContentPath() + relativePath;
+	}
+
+	public static String getAppname() {
+		return ParamUtil.getAppName();
+	}
+
+	public ServerHttpAgent(ServerListManager mgr) {
+		serverListMgr = mgr;
+	}
+	
+	public ServerHttpAgent(ServerListManager mgr, Properties properties) {
+		serverListMgr = mgr;
+		String ak = properties.getProperty(PropertyKeyConst.ACCESS_KEY);
+		if (StringUtils.isBlank(ak)) {
+			accessKey = SpasAdapter.getAk();
+		} else {
+			accessKey = ak;
+		}
+
+		String sk = properties.getProperty(PropertyKeyConst.SECRET_KEY);
+		if (StringUtils.isBlank(sk)) {
+			secretKey = SpasAdapter.getSk();
+		} else {
+			secretKey = sk;
+		}
+	}
+	
+	public ServerHttpAgent(Properties properties) throws NacosException {
+		String encodeTmp = properties.getProperty(PropertyKeyConst.ENCODE);
+		if (StringUtils.isBlank(encodeTmp)) {
+			encode = Constants.ENCODE;
+		} else {
+			encode = encodeTmp.trim();
+		}
+		serverListMgr = new ServerListManager(properties);
+		String ak = properties.getProperty(PropertyKeyConst.ACCESS_KEY);
+		if (StringUtils.isBlank(ak)) {
+			accessKey = SpasAdapter.getAk();
+		} else {
+			accessKey = ak;
+		}
+		
+		String sk = properties.getProperty(PropertyKeyConst.SECRET_KEY);
+		if (StringUtils.isBlank(sk)) {
+			secretKey = SpasAdapter.getSk();
+		} else {
+			secretKey = sk;
+		}
+	}
+
+	public synchronized void start() throws NacosException {
+		serverListMgr.start();
+	}
+	
+	private List<String> getSpasHeaders(List<String> paramValues) throws IOException {
+		List<String> newHeaders = new ArrayList<String>();
+		// STS 临时凭证鉴权的优先级高于 AK/SK 鉴权
+		if (STSConfig.getInstance().isSTSOn()) {
+			STSCredential sTSCredential = getSTSCredential();
+			accessKey = sTSCredential.accessKeyId;
+			secretKey = sTSCredential.accessKeySecret;
+			newHeaders.add("Spas-SecurityToken");
+			newHeaders.add(sTSCredential.securityToken);
+		}
+
+		if (StringUtils.isNotEmpty(accessKey) && StringUtils.isNotEmpty(secretKey)) {
+			newHeaders.add("Spas-AccessKey");
+			newHeaders.add(accessKey);
+			List<String> signHeaders = SpasAdapter.getSignHeaders(paramValues, secretKey);
+			if (signHeaders != null) {
+				newHeaders.addAll(signHeaders);
+			}
+		}
+		return newHeaders;
+	}
+
+	private STSCredential getSTSCredential() throws IOException {
+		boolean cacheSecurityCredentials = STSConfig.getInstance().isCacheSecurityCredentials();
+		if (cacheSecurityCredentials && sTSCredential != null) {
+			long currentTime = System.currentTimeMillis();
+			long expirationTime = sTSCredential.expiration.getTime();
+			int timeToRefreshInMillisecond = STSConfig.getInstance().getTimeToRefreshInMillisecond();
+			if (expirationTime - currentTime > timeToRefreshInMillisecond) {
+				return sTSCredential;
+			}
+		}
+		String stsResponse = getSTSResponse();
+		STSCredential stsCredentialTmp = (STSCredential)JSONUtils.deserializeObject(stsResponse,
+			new TypeReference<STSCredential>() {});
+		sTSCredential = stsCredentialTmp;
+		log.info("getSTSCredential", "code:{}, accessKeyId:{}, lastUpdated:{}, expiration:{}", sTSCredential.getCode(),
+			sTSCredential.getAccessKeyId(), sTSCredential.getLastUpdated(), sTSCredential.getExpiration());
+		return sTSCredential;
+	}
+
+	private static String getSTSResponse() throws IOException {
+		String securityCredentials = STSConfig.getInstance().getSecurityCredentials();
+		if (securityCredentials != null) {
+			return securityCredentials;
+		}
+		String securityCredentialsUrl = STSConfig.getInstance().getSecurityCredentialsUrl();
+		HttpURLConnection conn = null;
+		int respCode;
+		String response;
+		try {
+			conn = (HttpURLConnection)new URL(securityCredentialsUrl).openConnection();
+			conn.setRequestMethod("GET");
+			conn.setConnectTimeout(ParamUtil.getConnectTimeout() > 100 ? ParamUtil.getConnectTimeout() : 100);
+			conn.setReadTimeout(1000);
+			conn.connect();
+			respCode = conn.getResponseCode();
+			if (HttpURLConnection.HTTP_OK == respCode) {
+				response = IOUtils.toString(conn.getInputStream(), Constants.ENCODE);
+			} else {
+				response = IOUtils.toString(conn.getErrorStream(), Constants.ENCODE);
+			}
+		} catch (IOException e) {
+			log.error("500", "can not get security credentials", e);
+			throw e;
+		} finally {
+			if (null != conn) {
+				conn.disconnect();
+			}
+		}
+		if (HttpURLConnection.HTTP_OK == respCode) {
+			return response;
+		}
+		log.error(respCode + "", "can not get security credentials, securityCredentialsUrl:{}, response:{}",
+			new Object[] {securityCredentialsUrl, response});
+		throw new IOException("can not get security credentials, responseCode: " + respCode + ", response: " + response);
+	}
+	
+	public String getName() {
+		return serverListMgr.getName();
+	}
+
+	public String getNamespace() {
+		return serverListMgr.getNamespace();
+	}
+	public String getTenant() {
+		return serverListMgr.getTenant();
+	}
+
+	public String getEncode() {
+		return encode;
+	}
+
+	@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+	private static class STSCredential {
+		@JsonProperty(value = "AccessKeyId")
+		private String accessKeyId;
+		@JsonProperty(value = "AccessKeySecret")
+		private String accessKeySecret;
+		@JsonProperty(value = "Expiration")
+		private Date expiration;
+		@JsonProperty(value = "SecurityToken")
+		private String securityToken;
+		@JsonProperty(value = "LastUpdated")
+		private Date lastUpdated;
+		@JsonProperty(value = "Code")
+		private String code;
+
+		public String getAccessKeyId() {
+			return accessKeyId;
+		}
+
+		public Date getExpiration() {
+			return expiration;
+		}
+
+		public Date getLastUpdated() {
+			return lastUpdated;
+		}
+
+		public String getCode() {
+			return code;
+		}
+
+		public String toString() {
+			return "STSCredential{" +
+				"accessKeyId='" + accessKeyId + '\'' +
+				", accessKeySecret='" + accessKeySecret + '\'' +
+				", expiration=" + expiration +
+				", securityToken='" + securityToken + '\'' +
+				", lastUpdated=" + lastUpdated +
+				", code='" + code + '\'' +
+				'}';
+		}
+	}
+	
+	private String accessKey;
+	private String secretKey;
+	private String encode;
+	private volatile STSCredential sTSCredential;
+	final ServerListManager serverListMgr;
+
+}

client/src/main/java/com/alibaba/nacos/client/config/impl/ServerListManager.java

@@ -0,0 +1,432 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import java.io.IOException;
+import java.io.StringReader;
+import java.net.HttpURLConnection;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Properties;
+import java.util.Random;
+import java.util.concurrent.TimeUnit;
+
+import com.alibaba.nacos.api.PropertyKeyConst;
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.client.config.impl.EventDispatcher.ServerlistChangeEvent;
+import com.alibaba.nacos.client.config.impl.HttpSimpleClient.HttpResult;
+import com.alibaba.nacos.client.config.utils.IOUtils;
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+import com.alibaba.nacos.client.utils.EnvUtil;
+import com.alibaba.nacos.client.utils.ParamUtil;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
+
+/**
+ * Serverlist Manager
+ * 
+ * @author Nacos
+ */
+public class ServerListManager {
+    
+	final static public Logger log = LogUtils.logger(ServerListManager.class);
+	public ServerListManager() {
+		isFixed = false;
+		isStarted = false;
+		name = DEFAULT_NAME;
+	}
+
+	public ServerListManager(List<String> fixed) {
+		this(fixed, null);
+	}
+    
+	public ServerListManager(List<String> fixed, String namespace) {
+		isFixed = true;
+		isStarted = true;
+		List<String> serverAddrs = new ArrayList<String>();
+		for (String serverAddr : fixed) {
+			String[] serverAddrArr = serverAddr.split(":");
+			if (serverAddrArr.length == 1) {
+				serverAddrs.add(serverAddrArr[0] + ":" + ParamUtil.getDefaultServerPort());
+			} else {
+				serverAddrs.add(serverAddr);
+			}
+		}
+		serverUrls = new ArrayList<String>(serverAddrs);
+		if (StringUtils.isBlank(namespace)) {
+			name = FIXED_NAME + "-" + getFixedNameSuffix(serverAddrs.toArray(new String[serverAddrs.size()]));
+		} else {
+			this.namespace = namespace;
+			name = FIXED_NAME + "-" + getFixedNameSuffix(serverAddrs.toArray(new String[serverAddrs.size()])) + "-"
+					+ namespace;
+		}
+	}
+
+	public ServerListManager(String host, int port) {
+		isFixed = false;
+		isStarted = false;
+		name = CUSTOM_NAME + "-" + host + "-" + port;
+		addressServerUrl = String.format("http://%s:%d/%s/%s", host, port, contentPath, serverListName);
+	}
+
+	public ServerListManager(String endpoint) throws NacosException {
+		this(endpoint, null);
+	}
+
+	public ServerListManager(String endpoint, String namespace) throws NacosException {
+		isFixed = false;
+		isStarted = false;
+		if (StringUtils.isBlank(endpoint)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "endpoint is blank");
+		}
+		if (StringUtils.isBlank(namespace)) {
+			name = endpoint;
+			addressServerUrl = String.format("http://%s:%d/%s/%s", endpoint, endpointPort, contentPath,
+					serverListName);
+		} else {
+			if (StringUtils.isBlank(endpoint)) {
+				throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "endpoint is blank");
+			}
+			name = endpoint + "-" + namespace;
+			this.namespace = namespace;
+			this.tenant = namespace;
+			addressServerUrl = String.format("http://%s:%d/%s/%s?namespace=%s", endpoint, endpointPort, contentPath,
+					serverListName, namespace);
+		}
+	}
+	
+	public ServerListManager(Properties properties) throws NacosException {
+		isStarted = false;
+		String serverAddrsStr = properties.getProperty(PropertyKeyConst.SERVER_ADDR);
+		String namespace = properties.getProperty(PropertyKeyConst.NAMESPACE);
+		initParam(properties);
+		if (StringUtils.isNotEmpty(serverAddrsStr)) {
+			isFixed = true;
+			List<String> serverAddrs = new ArrayList<String>();
+			String[] serverAddrsArr = serverAddrsStr.split(",");
+			for (String serverAddr : serverAddrsArr) {
+				String[] serverAddrArr = serverAddr.split(":");
+				if (serverAddrArr.length == 1) {
+					serverAddrs.add(serverAddrArr[0] + ":" + ParamUtil.getDefaultServerPort());
+				} else {
+					serverAddrs.add(serverAddr);
+				}
+			}
+			serverUrls = serverAddrs;
+			if (StringUtils.isBlank(namespace)) {
+				name = FIXED_NAME + "-" + getFixedNameSuffix(serverUrls.toArray(new String[serverUrls.size()]));
+			} else {
+				this.namespace = namespace;
+				this.tenant = namespace;
+				name = FIXED_NAME + "-" + getFixedNameSuffix(serverUrls.toArray(new String[serverUrls.size()])) + "-"
+						+ namespace;
+			}
+		} else {
+			if (StringUtils.isBlank(endpoint)) {
+				throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "endpoint is blank");
+			}
+			isFixed = false;
+			if (StringUtils.isBlank(namespace)) {
+				name = endpoint;
+				addressServerUrl = String.format("http://%s:%d/%s/%s", endpoint, endpointPort, contentPath,
+						serverListName);
+			} else {
+				this.namespace = namespace;
+				this.tenant = namespace;
+				name = endpoint + "-" + namespace;
+				addressServerUrl = String.format("http://%s:%d/%s/%s?namespace=%s", endpoint, endpointPort,
+						contentPath, serverListName, namespace);
+			}
+		}
+	}
+	
+	private void initParam(Properties properties) {
+		String endpointTmp = properties.getProperty(PropertyKeyConst.ENDPOINT);
+		if (!StringUtils.isBlank(endpointTmp)) {
+			endpoint = endpointTmp;
+		}
+		String contentPathTmp = properties.getProperty(PropertyKeyConst.CONTEXT_PATH);
+		if (!StringUtils.isBlank(contentPathTmp)) {
+			contentPath = contentPathTmp;
+		}
+		String serverListNameTmp = properties.getProperty(PropertyKeyConst.CLUSTER_NAME);
+		if (!StringUtils.isBlank(serverListNameTmp)) {
+			serverListName = serverListNameTmp;
+		}
+	}
+	
+    public synchronized void start() throws NacosException {
+    	
+        if (isStarted || isFixed) {
+            return;
+        }
+
+		GetServerListTask getServersTask = new GetServerListTask(addressServerUrl);
+		for (int i = 0; i < initServerlistRetryTimes && serverUrls.isEmpty(); ++i) {
+			getServersTask.run();
+			try {
+				this.wait((i + 1) * 100L);
+			} catch (Exception e) {
+				log.warn("get serverlist fail,url: " + addressServerUrl);
+			}
+		}
+
+		if (serverUrls.isEmpty()) {
+			log.error("NACOS-0008", LoggerHelper.getErrorCodeStr("NACOS", "NACOS-0008", "环境问题",
+					"fail to get NACOS-server serverlist! env:" + name + ", not connnect url:" + addressServerUrl));
+			log.error(name, "NACOS-XXXX", "[init-serverlist] fail to get NACOS-server serverlist!");
+			throw new NacosException(NacosException.SERVER_ERROR,
+					"fail to get NACOS-server serverlist! env:" + name + ", not connnect url:" + addressServerUrl);
+		}
+
+        TimerService.scheduleWithFixedDelay(getServersTask, 0L, 30L, TimeUnit.SECONDS);
+        isStarted = true;
+    }
+    
+    Iterator<String> iterator() {
+        if (serverUrls.isEmpty()) {
+            log.error(name, "NACOS-XXXX", "[iterator-serverlist] No server address defined!");
+        }
+        return new ServerAddressIterator(serverUrls);
+    }
+    
+
+    class GetServerListTask implements Runnable {
+        final String url;
+        
+        GetServerListTask(String url) {
+            this.url = url;
+        }
+        
+        @Override
+		public void run() {
+			/**
+			 * get serverlist from nameserver
+			 */
+            try {
+                updateIfChanged(getApacheServerList(url, name));
+            } catch (Exception e) {
+                log.error(name, "NACOS-XXXX", "[update-serverlist] failed to update serverlist from address server!", e);
+            }
+        }
+    }
+    
+    private void updateIfChanged(List<String> newList) {
+        if (null == newList || newList.isEmpty()) {
+        	
+        	log.warn("NACOS-0001", LoggerHelper.getErrorCodeStr("NACOS", "NACOS-0001", "环境问题","[update-serverlist] current serverlist from address server is empty!!!"));
+            log.warn(name, "[update-serverlist] current serverlist from address server is empty!!!");
+            return;
+        }
+		/**
+		 * no change
+		 */
+        if (newList.equals(serverUrls)) { 
+            return;
+        }
+        serverUrls = new ArrayList<String>(newList);
+        currentServerAddr = iterator().next();
+        
+        EventDispatcher.fireEvent(new ServerlistChangeEvent());
+        log.info(name, "[update-serverlist] serverlist updated to {}", serverUrls);
+    }
+
+    private List<String> getApacheServerList(String url, String name) {
+        try {
+            HttpResult httpResult = HttpSimpleClient.httpGet(url, null, null, null, 3000);
+            
+			if (HttpURLConnection.HTTP_OK == httpResult.code) {
+				if (DEFAULT_NAME.equals(name) ) {
+					EnvUtil.setSelfEnv(httpResult.headers);
+				}
+                List<String> lines = IOUtils.readLines(new StringReader(httpResult.content));
+				List<String> result = new ArrayList<String>(lines.size());
+				for (String serverAddr : lines) {
+					if (null == serverAddr || serverAddr.trim().isEmpty()) {
+						continue;
+					} else {
+						String[] ipPort = serverAddr.trim().split(":");
+						String ip = ipPort[0].trim();
+						if (ipPort.length == 1) {
+							result.add(ip + ":" + ParamUtil.getDefaultServerPort());
+						} else {
+							result.add(serverAddr);
+						}
+					}
+				}
+                return result;
+            } else {
+                log.error(addressServerUrl, "NACOS-XXXX", "[check-serverlist] error. code={}", httpResult.code);
+                return null;
+            }
+        } catch (IOException e) {
+        	log.error("NACOS-0001", LoggerHelper.getErrorCodeStr("NACOS", "NACOS-0001", "环境问题",e.toString()));
+            log.error(addressServerUrl, "NACOS-XXXX", "[check-serverlist] exception. msg={}", e.toString(), e);
+            return null;
+        }
+    }
+    
+    String getUrlString() {
+        return serverUrls.toString();
+    }
+
+    String getFixedNameSuffix(String... serverIps) {
+        StringBuilder sb = new StringBuilder();
+        String split = "";
+        for (String serverIp : serverIps) {
+            sb.append(split);
+            sb.append(serverIp);
+            split = "-";
+        }
+        return sb.toString();
+    }
+
+	@Override
+    public String toString() {
+        return "ServerManager-" + name + "-" +getUrlString();
+    }
+
+	public boolean contain(String ip){
+		
+		return  serverUrls.contains(ip);
+	}
+
+	public void refreshCurrentServerAddr() {
+		currentServerAddr = iterator().next();
+	}
+
+	public String getCurrentServerAddr() {
+		if (StringUtils.isBlank(currentServerAddr)) {
+			currentServerAddr = iterator().next();
+		}
+		return currentServerAddr;
+	}
+
+	
+	public String getContentPath() {
+		return contentPath;
+	}
+	
+	public String getName() {
+		return name;
+	}
+	
+	public String getNamespace() {
+		return namespace;
+	}
+
+	public String getTenant() {
+		return tenant;
+	}
+	
+	/**
+	 * 不同环境的名称
+	 */
+	private String name;
+	private String namespace = "";
+	private String tenant = "";
+    static public final String DEFAULT_NAME = "default";
+    static public final String CUSTOM_NAME = "custom";
+    static public final String FIXED_NAME = "fixed";
+    private int initServerlistRetryTimes = 5;
+	/**
+	 * 和其他server的连接超时和socket超时
+	 */
+    static final int TIMEOUT = 5000;
+    
+    final boolean isFixed;
+	boolean isStarted = false;
+	private String endpoint;
+	private int endpointPort = 8080;
+	private String contentPath = ParamUtil.getDefaultContextPath();
+	private String serverListName = ParamUtil.getDefaultNodesPath();
+    volatile List<String> serverUrls = new ArrayList<String>();
+
+    private volatile String currentServerAddr;
+    
+	public String serverPort = ParamUtil.getDefaultServerPort();
+    
+    public String addressServerUrl;
+
+}
+
+
+/**
+ * 对地址列表排序，同机房优先。 
+ */
+class ServerAddressIterator implements Iterator<String> {
+
+    static class RandomizedServerAddress implements Comparable<RandomizedServerAddress> {
+        static Random random = new Random();
+        
+        String serverIp;
+        int priority = 0;
+        int seed;
+        
+		public RandomizedServerAddress(String ip) {
+			try {
+				this.serverIp = ip;
+				/**
+				 * change random scope from 32 to Integer.MAX_VALUE to fix load balance issue
+				 */
+				this.seed = random.nextInt(Integer.MAX_VALUE);
+			} catch (Exception e) {
+				throw new RuntimeException(e);
+			}
+		}
+
+        @Override
+        @SuppressFBWarnings("EQ_COMPARETO_USE_OBJECT_EQUALS")
+        public int compareTo(RandomizedServerAddress other) {
+            if (this.priority != other.priority) {
+                return other.priority - this.priority;
+            } else {
+                return other.seed - this.seed;
+            }
+        }
+    }
+
+    public ServerAddressIterator(List<String> source) {
+        sorted = new ArrayList<RandomizedServerAddress>();
+        for (String address : source) {
+            sorted.add(new RandomizedServerAddress(address));
+        }
+        Collections.sort(sorted);
+        iter = sorted.iterator();
+    }
+
+    public boolean hasNext() {
+        return iter.hasNext();
+    }
+
+    public String next() {
+        return iter.next().serverIp;
+    }
+
+    public void remove() {
+        throw new UnsupportedOperationException();
+    }
+    
+    final List<RandomizedServerAddress> sorted;
+    final Iterator<RandomizedServerAddress> iter;
+}
+

client/src/main/java/com/alibaba/nacos/client/config/impl/SpasAdapter.java

@@ -0,0 +1,111 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import javax.crypto.Mac;
+import javax.crypto.SecretKey;
+import javax.crypto.spec.SecretKeySpec;
+
+import com.alibaba.nacos.client.config.common.Constants;
+import com.alibaba.nacos.client.identify.Base64;
+import com.alibaba.nacos.client.identify.CredentialService;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+/**
+ * 适配spas接口
+ * 
+ * @author Nacos
+ *
+ */
+public class SpasAdapter {
+	
+	public static List<String> getSignHeaders(String resource, String secretKey) {
+		List<String> header = new ArrayList<String>();
+		String timeStamp = String.valueOf(System.currentTimeMillis());
+		header.add("Timestamp");
+		header.add(timeStamp);
+		if (secretKey != null) {
+			header.add("Spas-Signature");
+			String signature = "";
+			if (StringUtils.isBlank(resource)) {
+				signature = signWithhmacSHA1Encrypt(timeStamp, secretKey);
+			} else {
+				signature = signWithhmacSHA1Encrypt(resource + "+" + timeStamp, secretKey);
+			}
+			header.add(signature);
+		}
+		return header;
+	}
+	
+	
+	public static List<String> getSignHeaders(List<String> paramValues, String secretKey) {
+		if (null == paramValues) {
+			return null;
+		}
+		Map<String, String> signMap = new HashMap<String, String>(5);
+		for (Iterator<String> iter = paramValues.iterator(); iter.hasNext();) {
+			String key = iter.next();
+			if (TENANT_KEY.equals(key) || GROUP_KEY.equals(key)) {
+				signMap.put(key, iter.next());
+			} else {
+				iter.next();
+			}
+		}
+		String resource = "";
+		if (signMap.size() > 1) {
+			resource = signMap.get(TENANT_KEY) + "+" + signMap.get(GROUP_KEY);
+		} else {
+			if (!StringUtils.isBlank(signMap.get(GROUP_KEY))) {
+				resource = signMap.get(GROUP_KEY);
+			}
+		}
+		return getSignHeaders(resource, secretKey);
+	}
+
+	public static String getSk() {
+		return CredentialService.getInstance().getCredential().getSecretKey();
+	}
+
+	public static String getAk() {
+		return CredentialService.getInstance().getCredential().getAccessKey();
+	}
+	
+	public static String signWithhmacSHA1Encrypt(String encryptText, String encryptKey) {
+		try {
+			byte[] data = encryptKey.getBytes("UTF-8");
+			// 根据给定的字节数组构造一个密钥,第二参数指定一个密钥算法的名称
+			SecretKey secretKey = new SecretKeySpec(data, "HmacSHA1");
+			// 生成一个指定 Mac 算法 的 Mac 对象
+			Mac mac = Mac.getInstance("HmacSHA1");
+			// 用给定密钥初始化 Mac 对象
+			mac.init(secretKey);
+			byte[] text = encryptText.getBytes("UTF-8");
+			byte[] textFinal = mac.doFinal(text);
+			// 完成 Mac 操作, base64编码，将byte数组转换为字符串
+			return new String(Base64.encodeBase64(textFinal), Constants.ENCODE);
+		} catch (Exception e) {
+			throw new RuntimeException("signWithhmacSHA1Encrypt fail", e);
+		}
+	}
+	
+	private static String GROUP_KEY = "group";
+	private static String TENANT_KEY = "tenant";
+}

client/src/main/java/com/alibaba/nacos/client/config/impl/TimerService.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.impl;
+
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
+
+
+/**
+ * Time Service
+ * @author Nacos
+ *
+ */
+public class TimerService {
+
+    static public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command, long initialDelay,
+            long delay, TimeUnit unit) {
+        return scheduledExecutor.scheduleWithFixedDelay(command, initialDelay, delay, unit);
+    }
+    
+    @SuppressWarnings("PMD.ThreadPoolCreationRule")
+    static ScheduledExecutorService scheduledExecutor = Executors
+            .newSingleThreadScheduledExecutor(new ThreadFactory() {
+                public Thread newThread(Runnable r) {
+                    Thread t = new Thread(r);
+                    t.setName("com.alibaba.nacos.client.Timer");
+                    t.setDaemon(true);
+                    return t;
+                }
+            });
+    
+}

client/src/main/java/com/alibaba/nacos/client/config/listener/impl/PropertiesListener.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.listener.impl;
+
+import com.alibaba.nacos.api.config.listener.AbstractListener;
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+import java.io.IOException;
+import java.io.StringReader;
+import java.util.Properties;
+
+/**
+ * Properties Listener
+ * 
+ * @author Nacos
+ *
+ */
+@SuppressWarnings("PMD.AbstractClassShouldStartWithAbstractNamingRule")
+public abstract class PropertiesListener extends AbstractListener {
+	final static public Logger log = LogUtils.logger(PropertiesListener.class);
+	
+    public void receiveConfigInfo(String configInfo) {
+        if (StringUtils.isEmpty(configInfo)) {
+            return;
+        }
+
+        Properties properties = new Properties();
+        try {
+            properties.load(new StringReader(configInfo));
+            innerReceive(properties);
+        }
+        catch (IOException e) {
+            log.error("NACOS-XXXX","load properties error：" + configInfo, e);
+        }
+
+    }
+
+	/**
+	 * properties type for receiver
+	 * 
+	 * @param properties
+	 *            properties
+	 */
+	public abstract void innerReceive(Properties properties);
+
+}

client/src/main/java/com/alibaba/nacos/client/config/utils/ConcurrentDiskUtil.java

@@ -0,0 +1,247 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.utils;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.nio.ByteBuffer;
+import java.nio.CharBuffer;
+import java.nio.channels.FileChannel;
+import java.nio.channels.FileLock;
+import java.nio.charset.Charset;
+import java.nio.charset.CharsetDecoder;
+
+import com.alibaba.nacos.client.config.common.Constants;
+import com.alibaba.nacos.client.logger.Logger;
+
+/**
+ * concurrent disk util;op file with file lock
+ * 
+ * @author configCenter
+ *
+ */
+public class ConcurrentDiskUtil {
+
+	/**
+	 * get file content
+	 * 
+	 * @param path
+	 *            file path
+	 * @param charsetName
+	 *            charsetName
+	 * @return content
+	 * @throws IOException
+	 *             IOException
+	 */
+	public static String getFileContent(String path, String charsetName)
+			throws IOException {
+		File file = new File(path);
+		return getFileContent(file, charsetName);
+	}
+
+	/**
+	 * get file content
+	 * 
+	 * @param file
+	 *            file
+	 * @param charsetName
+	 *            charsetName
+	 * @return content
+	 * @throws IOException
+	 *             IOException
+	 */
+	public static String getFileContent(File file, String charsetName)
+			throws IOException {
+		RandomAccessFile fis = null;
+		FileLock rlock = null;
+		try {
+			fis = new RandomAccessFile(file, "r");
+			FileChannel fcin = fis.getChannel();
+			int i = 0;
+			do {
+				try {
+					rlock = fcin.tryLock(0L, Long.MAX_VALUE, true);
+				} catch (Exception e) {
+					++i;
+					if (i > RETRY_COUNT) {
+						log.error("read {} fail;retryed time:{}",
+								file.getName(), i);
+						throw new IOException("read " + file.getAbsolutePath()
+								+ " conflict");
+					}
+					sleep(SLEEP_BASETIME * i);
+					log.warn("read {} conflict;retry time:{}", file.getName(),
+							i);
+				}
+			} while (null == rlock);
+			int fileSize = (int) fcin.size();
+			ByteBuffer byteBuffer = ByteBuffer.allocate(fileSize);
+			fcin.read(byteBuffer);
+			byteBuffer.flip();
+			return byteBufferToString(byteBuffer, charsetName);
+		} finally {
+			if (rlock != null) {
+				rlock.release();
+				rlock = null;
+			}
+			if (fis != null) {
+				fis.close();
+				fis = null;
+			}
+		}
+	}
+
+	/**
+	 * write file content
+	 * 
+	 * @param path
+	 *            file path
+	 * @param content
+	 *            content
+	 * @param charsetName
+	 *            charsetName
+	 * @return whether write ok
+	 * @throws IOException
+	 *             IOException
+	 */
+	public static Boolean writeFileContent(String path, String content,
+			String charsetName) throws IOException {
+		File file = new File(path);
+		return writeFileContent(file, content, charsetName);
+	}
+
+	/**
+	 * write file content
+	 * 
+	 * @param file
+	 *            file
+	 * @param content
+	 *            content
+	 * @param charsetName
+	 *            charsetName
+	 * @return whether write ok
+	 * @throws IOException
+	 *             IOException
+	 */
+	public static Boolean writeFileContent(File file, String content,
+			String charsetName) throws IOException {
+		if (!file.exists()) {
+			boolean isCreateOk = file.createNewFile();
+			if (!isCreateOk) {
+				return false;
+			}
+		}
+		FileChannel channel = null;
+		FileLock lock = null;
+		RandomAccessFile raf = null;
+		try {
+			raf = new RandomAccessFile(file, "rw");
+			channel = raf.getChannel();
+			int i = 0;
+			do {
+				try {
+					lock = channel.tryLock();
+				} catch (Exception e) {
+					++i;
+					if (i > RETRY_COUNT) {
+						log.error("write {} fail;retryed time:{}",
+								file.getName(), i);
+						throw new IOException("write " + file.getAbsolutePath()
+								+ " conflict");
+					}
+					sleep(SLEEP_BASETIME * i);
+					log.warn("write {} conflict;retry time:{}", file.getName(),
+							i);
+				}
+			} while (null == lock);
+
+			ByteBuffer sendBuffer = ByteBuffer.wrap(content
+					.getBytes(charsetName));
+			while (sendBuffer.hasRemaining()) {
+				channel.write(sendBuffer);
+			}
+			channel.truncate(content.length());
+		} catch (FileNotFoundException e) {
+			throw new IOException("file not exist");
+		} finally {
+			if (lock != null) {
+				try {
+					lock.release();
+					lock = null;
+				} catch (IOException e) {
+					log.warn("close wrong", e);
+				}
+			}
+			if (channel != null) {
+				try {
+					channel.close();
+					channel = null;
+				} catch (IOException e) {
+					log.warn("close wrong", e);
+				}
+			}
+			if (raf != null) {
+				try {
+					raf.close();
+					raf = null;
+				} catch (IOException e) {
+					log.warn("close wrong", e);
+				}
+			}
+
+		}
+		return true;
+	}
+
+	/**
+	 * transfer ByteBuffer to String
+	 * 
+	 * @param buffer
+	 *            buffer
+	 * @param charsetName
+	 *            charsetName
+	 * @return String
+	 * @throws IOException
+	 *             IOException
+	 */
+	public static String byteBufferToString(ByteBuffer buffer,
+			String charsetName) throws IOException {
+		Charset charset = null;
+		CharsetDecoder decoder = null;
+		CharBuffer charBuffer = null;
+		charset = Charset.forName(charsetName);
+		decoder = charset.newDecoder();
+		charBuffer = decoder.decode(buffer.asReadOnlyBuffer());
+		return charBuffer.toString();
+	}
+
+	private static void sleep(int time) {
+		try {
+			Thread.sleep(time);
+		} catch (InterruptedException e) {
+			log.warn("sleep wrong", e);
+		}
+	}
+
+	static final public Logger log = LogUtils.logger(ConcurrentDiskUtil.class);
+	static final int RETRY_COUNT = 10;
+	/**
+	 * ms
+	 */
+	static final int SLEEP_BASETIME = 10;
+}

client/src/main/java/com/alibaba/nacos/client/config/utils/ContentUtils.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.utils;
+
+import static com.alibaba.nacos.client.config.common.Constants.WORD_SEPARATOR;
+
+import com.alibaba.nacos.client.config.common.Constants;
+
+/**
+ * Content Util
+ * 
+ * @author Nacos
+ *
+ */
+public class ContentUtils {
+
+    public static void verifyIncrementPubContent(String content) {
+
+        if (content == null || content.length() == 0) {
+            throw new IllegalArgumentException("发布/删除内容不能为空");
+        }
+        for (int i = 0; i < content.length(); i++) {
+            char c = content.charAt(i);
+            if (c == '\r' || c == '\n') {
+                throw new IllegalArgumentException("发布/删除内容不能包含回车和换行");
+            }
+            if (c == Constants.WORD_SEPARATOR.charAt(0)) {
+                throw new IllegalArgumentException("发布/删除内容不能包含(char)2");
+            }
+        }
+    }
+
+
+    public static String getContentIdentity(String content) {
+        int index = content.indexOf(WORD_SEPARATOR);
+        if (index == -1) {
+            throw new IllegalArgumentException("内容没有包含分隔符");
+        }
+        return content.substring(0, index);
+    }
+
+
+    public static String getContent(String content) {
+        int index = content.indexOf(WORD_SEPARATOR);
+        if (index == -1) {
+            throw new IllegalArgumentException("内容没有包含分隔符");
+        }
+        return content.substring(index + 1);
+    }
+
+
+    public static String truncateContent(String content) {
+        if (content == null) {
+            return "";
+        }
+        else if (content.length() <= SHOW_CONTENT_SIZE) {
+            return content;
+        }
+        else {
+			return content.substring(0, SHOW_CONTENT_SIZE) + "...";
+        }
+    }
+
+	private static int SHOW_CONTENT_SIZE = 100;
+}

client/src/main/java/com/alibaba/nacos/client/config/utils/IOUtils.java

@@ -0,0 +1,151 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.utils;
+
+import java.io.BufferedReader;
+import java.io.CharArrayWriter;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.Reader;
+import java.io.Writer;
+import java.util.ArrayList;
+import java.util.List;
+
+import com.alibaba.nacos.client.config.common.Constants;
+
+
+/**
+ * IO Util
+ * 
+ * @author Nacos
+ *
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public class IOUtils {
+
+    static public String toString(InputStream input, String encoding) throws IOException {
+        return (null == encoding) ? toString(new InputStreamReader(input, Constants.ENCODE))
+                : toString(new InputStreamReader(input, encoding));
+    }
+    
+    static public String toString(Reader reader) throws IOException {
+        CharArrayWriter sw = new CharArrayWriter();
+        copy(reader, sw);
+        return sw.toString();
+    }
+
+    static public long copy(Reader input, Writer output) throws IOException {
+        char[] buffer = new char[1 << 12];
+        long count = 0;
+        for (int n = 0; (n = input.read(buffer)) >= 0;) {
+            output.write(buffer, 0, n);
+            count += n;
+        }
+        return count;
+    }
+
+    /**
+     * 从输入流读行列表。保证不返回NULL。
+     */
+    static public List<String> readLines(Reader input) throws IOException {
+        BufferedReader reader = toBufferedReader(input);
+        List<String> list = new ArrayList<String>();
+        String line = null;
+        for (;;) {
+            line = reader.readLine();
+            if (null != line) {
+                list.add(line);
+            } else {
+                break;
+            }
+        }
+        return list;
+    }
+
+    static private BufferedReader toBufferedReader(Reader reader) {
+        return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(
+                reader);
+    }
+
+    public static void delete(File fileOrDir) throws IOException {
+        if (fileOrDir == null) {
+            return;
+        }
+
+        if (fileOrDir.isDirectory()) {
+            cleanDirectory(fileOrDir);
+        }
+
+		boolean isDeleteOk = fileOrDir.delete();
+		if (!isDeleteOk) {
+			throw new IOException("delete fail");
+		}
+    }
+    
+    /**
+     * 清理目录下的内容
+     */
+    public static void cleanDirectory(File directory) throws IOException {
+        if (!directory.exists()) {
+            String message = directory + " does not exist";
+            throw new IllegalArgumentException(message);
+        }
+
+        if (!directory.isDirectory()) {
+            String message = directory + " is not a directory";
+            throw new IllegalArgumentException(message);
+        }
+
+        File[] files = directory.listFiles();
+		/**
+		 * null if security restricted
+		 */
+		if (files == null) {
+            throw new IOException("Failed to list contents of " + directory);
+        }
+
+        IOException exception = null;
+        for (File file : files) {
+            try {
+                delete(file);
+            } catch (IOException ioe) {
+                exception = ioe;
+            }
+        }
+
+        if (null != exception) {
+            throw exception;
+        }
+    }
+
+    public static void writeStringToFile(File file, String data, String encoding)
+            throws IOException {
+        OutputStream os = null;
+        try {
+            os = new FileOutputStream(file);
+            os.write(data.getBytes(encoding));
+        } finally {
+            if (null != os) {
+                os.close();
+            }
+        }
+    }
+}
+

client/src/main/java/com/alibaba/nacos/client/config/utils/JVMUtil.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.utils;
+
+import com.alibaba.nacos.client.logger.Logger;
+
+/**
+ * Get jvm config
+ * 
+ * @author Nacos
+ *
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public class JVMUtil {
+
+	/**
+	 * whether is multi instance
+	 * 
+	 * @return whether multi
+	 */
+	public static Boolean isMultiInstance() {
+		return isMultiInstance;
+	}
+
+	private static Boolean isMultiInstance = false;
+	private static String TRUE = "true";
+	static final public Logger log = LogUtils.logger(JVMUtil.class);
+
+	static {
+		String multiDeploy = System.getProperty("isMultiInstance", "false");
+		if (TRUE.equals(multiDeploy)) {
+			isMultiInstance = true;
+		}
+		log.info("isMultiInstance:{}", isMultiInstance);
+	}
+}

client/src/main/java/com/alibaba/nacos/client/config/utils/LogUtils.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.utils;
+
+import com.alibaba.nacos.client.config.common.Constants;
+import com.alibaba.nacos.client.logger.Level;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.LoggerFactory;
+
+/**
+ * Log Util
+ * 
+ * @author Nacos
+ *
+ */
+public class LogUtils {
+
+	static int JM_LOG_RETAIN_COUNT = 7;
+	static String JM_LOG_FILE_SIZE = "10MB";
+
+    static {
+    	String tmp = "7";
+        try {
+			/**
+			 * change timeout from 100 to 200
+			 */
+            tmp = System.getProperty("JM.LOG.RETAIN.COUNT","7");
+            JM_LOG_RETAIN_COUNT = Integer.parseInt(tmp);
+        } catch (NumberFormatException e) {
+			e.printStackTrace();
+			throw e;
+        }
+        
+        JM_LOG_FILE_SIZE = System.getProperty("JM.LOG.FILE.SIZE","10MB"); 
+    	
+        // logger init
+        Logger logger = LoggerFactory.getLogger("com.alibaba.nacos.client.config");
+        logger.setLevel(Level.INFO);
+        logger.setAdditivity(false);
+        logger.activateAppenderWithSizeRolling("nacos", "config.log", Constants.ENCODE, JM_LOG_FILE_SIZE, JM_LOG_RETAIN_COUNT);
+    }
+
+   public static Logger logger(Class<?> clazz) {
+       return LoggerFactory.getLogger(clazz);
+   }
+}

client/src/main/java/com/alibaba/nacos/client/config/utils/MD5.java

@@ -0,0 +1,145 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.utils;
+
+import java.io.UnsupportedEncodingException;
+import java.security.MessageDigest;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.locks.ReentrantLock;
+
+import com.alibaba.nacos.client.config.common.Constants;
+
+/**
+ * MD5 util
+ * 
+ * @author Nacos
+ *
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public class MD5 {
+	private static int DIGITS_SIZE = 16;
+    private static char[] digits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
+
+    private static Map<Character, Integer> rDigits = new HashMap<Character, Integer>(16);
+    static {
+        for (int i = 0; i < digits.length; ++i) {
+            rDigits.put(digits[i], i);
+        }
+    }
+
+    private static MD5 me = new MD5();
+    private MessageDigest mHasher;
+    private ReentrantLock opLock = new ReentrantLock();
+
+
+    private MD5() {
+        try {
+            mHasher = MessageDigest.getInstance("md5");
+        }
+        catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+
+    }
+
+
+    public static MD5 getInstance() {
+        return me;
+    }
+
+
+    public String getMD5String(String content) {
+        return bytes2string(hash(content));
+    }
+
+
+    public String getMD5String(byte[] content) {
+        return bytes2string(hash(content));
+    }
+
+
+    public byte[] getMD5Bytes(byte[] content) {
+        return hash(content);
+    }
+
+
+    /**
+     * 对字符串进行md5
+     * 
+     * @param str
+     * @return md5 byte[16]
+     */
+    public byte[] hash(String str) {
+        opLock.lock();
+        try {
+            byte[] bt = mHasher.digest(str.getBytes(Constants.ENCODE));
+            if (null == bt || bt.length != DIGITS_SIZE) {
+                throw new IllegalArgumentException("md5 need");
+            }
+            return bt;
+        }
+        catch (UnsupportedEncodingException e) {
+            throw new RuntimeException("unsupported utf-8 encoding", e);
+        }
+        finally {
+            opLock.unlock();
+        }
+    }
+
+
+    /**
+     * 对二进制数据进行md5
+     * 
+     * @param str
+     * @return md5 byte[16]
+     */
+    public byte[] hash(byte[] data) {
+        opLock.lock();
+        try {
+            byte[] bt = mHasher.digest(data);
+            if (null == bt || bt.length != DIGITS_SIZE) {
+                throw new IllegalArgumentException("md5 need");
+            }
+            return bt;
+        }
+        finally {
+            opLock.unlock();
+        }
+    }
+
+
+    /**
+     * 将一个字节数组转化为可见的字符串
+     * 
+     * @param bt
+     * @return
+     */
+    public String bytes2string(byte[] bt) {
+        int l = bt.length;
+
+        char[] out = new char[l << 1];
+
+        for (int i = 0, j = 0; i < l; i++) {
+            out[j++] = digits[(0xF0 & bt[i]) >>> 4];
+            out[j++] = digits[0x0F & bt[i]];
+        }
+
+        return new String(out);
+    }
+
+
+}

client/src/main/java/com/alibaba/nacos/client/config/utils/ParamUtils.java

@@ -0,0 +1,154 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.utils;
+
+import java.util.List;
+
+import com.alibaba.nacos.api.exception.NacosException;
+import com.alibaba.nacos.client.utils.IPUtil;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+/**
+ * Param check util
+ * 
+ * @author Nacos
+ * 
+ */
+public class ParamUtils {
+
+    private static char[] validChars = new char[] { '_', '-', '.', ':' };
+
+
+    /**
+     * 白名单的方式检查, 合法的参数只能包含字母、数字、以及validChars中的字符, 并且不能为空
+     * 
+     * @param param
+     * @return
+     */
+    public static boolean isValid(String param) {
+        if (param == null) {
+            return false;
+        }
+        int length = param.length();
+        for (int i = 0; i < length; i++) {
+            char ch = param.charAt(i);
+            if (Character.isLetterOrDigit(ch)) {
+                continue;
+            }
+            else if (isValidChar(ch)) {
+                continue;
+            }
+            else {
+                return false;
+            }
+        }
+        return true;
+    }
+
+
+    private static boolean isValidChar(char ch) {
+        for (char c : validChars) {
+            if (c == ch) {
+                return true;
+            }
+        }
+        return false;
+    }
+    
+	public static void checkKeyParam(String dataId, String group) throws NacosException {
+		if (StringUtils.isBlank(dataId) || !ParamUtils.isValid(dataId)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "dataId invalid");
+		}
+		if (StringUtils.isBlank(group) || !ParamUtils.isValid(group)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "group invalid");
+		}
+	}
+	
+	public static void checkTDG(String tenant, String dataId, String group) throws NacosException {
+		checkTenant(tenant);
+		if (StringUtils.isBlank(dataId) || !ParamUtils.isValid(dataId)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "dataId invalid");
+		}
+		if (StringUtils.isBlank(group) || !ParamUtils.isValid(group)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "group invalid");
+		}
+	}
+	
+	public static void checkKeyParam(String dataId, String group, String datumId)
+			throws NacosException {
+		if (StringUtils.isBlank(dataId) || !ParamUtils.isValid(dataId)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "dataId invalid");
+		}
+		if (StringUtils.isBlank(group) || !ParamUtils.isValid(group)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "group invalid");
+		}
+		if (StringUtils.isBlank(datumId) || !ParamUtils.isValid(datumId)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "datumId invalid");
+		}
+	}
+    
+	public static void checkKeyParam(List<String> dataIds, String group) throws NacosException {
+		if (dataIds == null || dataIds.size() == 0) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "dataIds invalid");
+		}
+		for (String dataId : dataIds) {
+			if (StringUtils.isBlank(dataId) || !ParamUtils.isValid(dataId)) {
+				throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "dataId invalid");
+			}
+		}
+		if (StringUtils.isBlank(group) || !ParamUtils.isValid(group)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "group invalid");
+		}
+	}
+
+	public static void checkParam(String dataId, String group, String content) throws NacosException {
+		checkKeyParam(dataId, group);
+		if (StringUtils.isBlank(content)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "content invalid");
+		}
+	}
+    
+	public static void checkParam(String dataId, String group, String datumId, String content) throws NacosException {
+		checkKeyParam(dataId, group, datumId);
+		if (StringUtils.isBlank(content)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "content invalid");
+		}
+	}
+
+	public static void checkTenant(String tenant) throws NacosException {
+		if (StringUtils.isBlank(tenant) || !ParamUtils.isValid(tenant)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "tenant invalid");
+		}
+	}
+	
+	public static void checkBetaIps(String betaIps) throws NacosException {
+		if (StringUtils.isBlank(betaIps)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "betaIps invalid");
+		}
+		String[] ipsArr = betaIps.split(",");
+		for (String ip : ipsArr) {
+			if (!IPUtil.isIPV4(ip)) {
+				throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "betaIps invalid");
+			}
+		}
+	}
+
+	public static void checkContent(String content) throws NacosException {
+		if (StringUtils.isBlank(content)) {
+			throw new NacosException(NacosException.CLIENT_INVALID_PARAM, "content invalid");
+		}
+	}
+}

client/src/main/java/com/alibaba/nacos/client/config/utils/SnapShotSwitch.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.utils;
+
+import com.alibaba.nacos.client.config.impl.LocalConfigInfoProcessor;
+
+/**
+ * Snapshot switch
+ * 
+ * @author Nacos
+ *
+ */
+public class SnapShotSwitch {
+
+	/**
+	 * whether use local cache
+	 */
+	private static Boolean isSnapShot = true;
+
+	public static Boolean getIsSnapShot() {
+		return isSnapShot;
+	}
+
+	public static void setIsSnapShot(Boolean isSnapShot) {
+		SnapShotSwitch.isSnapShot = isSnapShot;
+		LocalConfigInfoProcessor.cleanAllSnapshot();
+	}
+	
+}

client/src/main/java/com/alibaba/nacos/client/config/utils/TenantUtil.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.config.utils;
+
+import com.alibaba.nacos.client.utils.StringUtils;
+
+/**
+ * Tenant Util
+ * 
+ * @author Nacos
+ *
+ */
+public class TenantUtil {
+
+	static String userTenant = "";
+	
+	static {
+		userTenant = System.getProperty("tenant.id", "");
+		if (StringUtils.isBlank(userTenant)) {
+			userTenant = System.getProperty("acm.namespace", "");
+		}
+	}
+
+	public static String getUserTenant() {
+		return userTenant;
+	}
+
+	public static void setUserTenant(String userTenant) {
+		TenantUtil.userTenant = userTenant;
+	}
+}

client/src/main/java/com/alibaba/nacos/client/identify/Base64.java

@@ -0,0 +1,707 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.identify;
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.io.UnsupportedEncodingException;
+
+/**
+* Provides Base64 encoding and decoding as defined by <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>.
+* 
+* <p>
+* This class implements section <cite>6.8. Base64 Content-Transfer-Encoding</cite> from RFC 2045 <cite>Multipurpose
+* Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies</cite> by Freed and Borenstein.
+* </p>
+* <p>
+* The class can be parameterized in the following manner with various constructors:
+* <ul>
+* <li>URL-safe mode: Default off.</li>
+* <li>Line length: Default 76. Line length that aren't multiples of 4 will still essentially end up being multiples of
+* 4 in the encoded data.
+* <li>Line separator: Default is CRLF ("\r\n")</li>
+* </ul>
+* </p>
+* <p>
+* Since this class operates directly on byte streams, and not character streams, it is hard-coded to only encode/decode
+* character encodings which are compatible with the lower 127 ASCII chart (ISO-8859-1, Windows-1252, UTF-8, etc).
+* </p>
+* <p>
+* This class is not thread-safe. Each thread should use its own instance.
+* </p>
+* 
+* @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>
+* @author Apache Software Foundation
+* @since 1.0
+* @version $Revision: 1080712 $
+*/
+public class Base64 {
+
+   /**
+    * BASE32 characters are 6 bits in length. 
+    * They are formed by taking a block of 3 octets to form a 24-bit string, 
+    * which is converted into 4 BASE64 characters.
+    */
+   private static final int BITS_PER_ENCODED_BYTE = 6;
+   private static final int BYTES_PER_UNENCODED_BLOCK = 3;
+   private static final int BYTES_PER_ENCODED_BLOCK = 4;
+
+   /**
+    * Chunk separator per RFC 2045 section 2.1.
+    *
+    * <p>
+    * N.B. The next major release may break compatibility and make this field private.
+    * </p>
+    * 
+    * @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045 section 2.1</a>
+    */
+   static final byte[] CHUNK_SEPARATOR = {'\r', '\n'};
+
+   /**
+    * This array is a lookup table that translates 6-bit positive integer index values into their "Base64 Alphabet"
+    * equivalents as specified in Table 1 of RFC 2045.
+    * 
+    * Thanks to "commons" project in ws.apache.org for this code.
+    * http://svn.apache.org/repos/asf/webservices/commons/trunk/modules/util/
+    */
+   private static final byte[] STANDARD_ENCODE_TABLE = {
+           'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
+           'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
+           'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
+           'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
+           '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
+   };
+
+   /**
+    * This is a copy of the STANDARD_ENCODE_TABLE above, but with + and /
+    * changed to - and _ to make the encoded Base64 results more URL-SAFE.
+    * This table is only used when the Base64's mode is set to URL-SAFE.
+    */    
+   private static final byte[] URL_SAFE_ENCODE_TABLE = {
+           'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
+           'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
+           'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
+           'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
+           '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '-', '_'
+   };
+
+   /**
+    * This array is a lookup table that translates Unicode characters drawn from the "Base64 Alphabet" (as specified in
+    * Table 1 of RFC 2045) into their 6-bit positive integer equivalents. Characters that are not in the Base64
+    * alphabet but fall within the bounds of the array are translated to -1.
+    * 
+    * Note: '+' and '-' both decode to 62. '/' and '_' both decode to 63. This means decoder seamlessly handles both
+    * URL_SAFE and STANDARD base64. (The encoder, on the other hand, needs to know ahead of time what to emit).
+    * 
+    * Thanks to "commons" project in ws.apache.org for this code.
+    * http://svn.apache.org/repos/asf/webservices/commons/trunk/modules/util/
+    */
+   private static final byte[] DECODE_TABLE = {
+           -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+           -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+           -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, 62, -1, 63, 52, 53, 54,
+           55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4,
+           5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
+           24, 25, -1, -1, -1, -1, 63, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34,
+           35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51
+   };
+
+   /**
+    * Base64 uses 6-bit fields. 
+    */
+   /** Mask used to extract 6 bits, used when encoding */
+   private static final int MASK_6BITS = 0x3f;
+
+   // The static final fields above are used for the original static byte[] methods on Base64.
+   // The private member fields below are used with the new streaming approach, which requires
+   // some state be preserved between calls of encode() and decode().
+
+   /**
+    * Encode table to use: either STANDARD or URL_SAFE. Note: the DECODE_TABLE above remains static because it is able
+    * to decode both STANDARD and URL_SAFE streams, but the encodeTable must be a member variable so we can switch
+    * between the two modes.
+    */
+   private final byte[] encodeTable;
+
+	/**
+	 * Only one decode table currently; keep for consistency with Base32 code
+	 */
+   private final byte[] decodeTable = DECODE_TABLE;
+
+   /**
+    * Line separator for encoding. Not used when decoding. Only used if lineLength > 0.
+    */
+   private final byte[] lineSeparator;
+
+   /**
+    * Convenience variable to help us determine when our buffer is going to run out of room and needs resizing.
+    * <code>decodeSize = 3 + lineSeparator.length;</code>
+    */
+   private final int decodeSize;
+
+   /**
+    * Convenience variable to help us determine when our buffer is going to run out of room and needs resizing.
+    * <code>encodeSize = 4 + lineSeparator.length;</code>
+    */
+   private final int encodeSize;
+
+   /**
+    * Place holder for the bytes we're dealing with for our based logic. 
+    * Bitwise operations store and extract the encoding or decoding from this variable.
+    */
+   private int bitWorkArea;
+
+   /**
+    * Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
+    * <p>
+    * When encoding the line length is 0 (no chunking), and the encoding table is STANDARD_ENCODE_TABLE.
+    * </p>
+    * 
+    * <p>
+    * When decoding all variants are supported.
+    * </p>
+    */
+   public Base64() {
+       this(0, CHUNK_SEPARATOR, false);
+   }
+
+   /**
+    * Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
+    * <p>
+    * When encoding the line length and line separator are given in the constructor, and the encoding table is
+    * STANDARD_ENCODE_TABLE.
+    * </p>
+    * <p>
+    * Line lengths that aren't multiples of 4 will still essentially end up being multiples of 4 in the encoded data.
+    * </p>
+    * <p>
+    * When decoding all variants are supported.
+    * </p>
+    * 
+    * @param lineLength
+    *            Each line of encoded data will be at most of the given length (rounded down to nearest multiple of 4).
+    *            If lineLength <= 0, then the output will not be divided into lines (chunks). Ignored when decoding.
+    * @param lineSeparator
+    *            Each line of encoded data will end with this sequence of bytes.
+    * @param urlSafe
+    *            Instead of emitting '+' and '/' we emit '-' and '_' respectively. urlSafe is only applied to encode
+    *            operations. Decoding seamlessly handles both modes.
+    * @throws IllegalArgumentException
+    *             The provided lineSeparator included some base64 characters. That's not going to work!
+    * @since 1.4
+    */
+   public Base64(int lineLength, byte[] lineSeparator, boolean urlSafe) {
+       chunkSeparatorLength = lineSeparator == null ? 0 : lineSeparator.length;
+       unencodedBlockSize = BYTES_PER_UNENCODED_BLOCK;
+       encodedBlockSize = BYTES_PER_ENCODED_BLOCK;
+       this.lineLength = (lineLength > 0  && chunkSeparatorLength > 0) ? (lineLength / encodedBlockSize) * encodedBlockSize : 0;
+       // TODO could be simplified if there is no requirement to reject invalid line sep when length <=0
+       // @see test case Base64Test.testConstructors() 
+       if (lineSeparator != null) {
+           if (containsAlphabetOrPad(lineSeparator)) {
+               String sep = null;
+               try {
+                   sep = new String(lineSeparator, "UTF-8");
+               } catch (UnsupportedEncodingException e) {
+               }
+               throw new IllegalArgumentException("lineSeparator must not contain base64 characters: [" + sep + "]");
+           }            
+           if (lineLength > 0){
+               this.encodeSize = BYTES_PER_ENCODED_BLOCK + lineSeparator.length;
+               this.lineSeparator = new byte[lineSeparator.length];
+               System.arraycopy(lineSeparator, 0, this.lineSeparator, 0, lineSeparator.length);
+           } else {
+               this.encodeSize = BYTES_PER_ENCODED_BLOCK;
+               this.lineSeparator = null;
+           }
+       } else {
+           this.encodeSize = BYTES_PER_ENCODED_BLOCK;
+           this.lineSeparator = null;
+       }
+       this.decodeSize = this.encodeSize - 1;
+       this.encodeTable = urlSafe ? URL_SAFE_ENCODE_TABLE : STANDARD_ENCODE_TABLE;
+   }
+
+   /**
+    * <p>
+    * Encodes all of the provided data, starting at inPos, for inAvail bytes. Must be called at least twice: once with
+    * the data to encode, and once with inAvail set to "-1" to alert encoder that EOF has been reached, so flush last
+    * remaining bytes (if not multiple of 3).
+    * </p>
+    * <p>
+    * Thanks to "commons" project in ws.apache.org for the bitwise operations, and general approach.
+    * http://svn.apache.org/repos/asf/webservices/commons/trunk/modules/util/
+    * </p>
+    * 
+    * @param in
+    *            byte[] array of binary data to base64 encode.
+    * @param inPos
+    *            Position to start reading data from.
+    * @param inAvail
+    *            Amount of bytes available from input for encoding.
+    */
+   void encode(byte[] in, int inPos, int inAvail) {
+       if (eof) {
+           return;
+       }
+       if (inAvail < 0) {
+           eof = true;
+           if (0 == modulus && lineLength == 0) {
+               return;
+           }
+           ensureBufferSize(encodeSize);
+           int savedPos = pos;
+           switch (modulus) {
+               case 1 :
+                   buffer[pos++] = encodeTable[(bitWorkArea >> 2) & MASK_6BITS];
+                   buffer[pos++] = encodeTable[(bitWorkArea << 4) & MASK_6BITS];
+				
+                   if (encodeTable == STANDARD_ENCODE_TABLE) {
+                       buffer[pos++] = PAD;
+                       buffer[pos++] = PAD;
+                   }
+                   break;
+
+               case 2 :
+                   buffer[pos++] = encodeTable[(bitWorkArea >> 10) & MASK_6BITS];
+                   buffer[pos++] = encodeTable[(bitWorkArea >> 4) & MASK_6BITS];
+                   buffer[pos++] = encodeTable[(bitWorkArea << 2) & MASK_6BITS];
+                   
+                   if (encodeTable == STANDARD_ENCODE_TABLE) {
+                       buffer[pos++] = PAD;
+                   }
+                   break;
+			   default:
+				   break;
+           }
+           currentLinePos += pos - savedPos; 
+			/**
+			 * if currentPos == 0 we are at the start of a line, so don't add CRLF
+			 */
+           if (lineLength > 0 && currentLinePos > 0) { 
+               System.arraycopy(lineSeparator, 0, buffer, pos, lineSeparator.length);
+               pos += lineSeparator.length;
+           }
+       } else {
+           for (int i = 0; i < inAvail; i++) {
+               ensureBufferSize(encodeSize);
+               modulus = (modulus+1) % BYTES_PER_UNENCODED_BLOCK;
+               int b = in[inPos++];
+               if (b < 0) {
+                   b += 256;
+               }
+               bitWorkArea = (bitWorkArea << 8) + b;
+               if (0 == modulus) {
+                   buffer[pos++] = encodeTable[(bitWorkArea >> 18) & MASK_6BITS];
+                   buffer[pos++] = encodeTable[(bitWorkArea >> 12) & MASK_6BITS];
+                   buffer[pos++] = encodeTable[(bitWorkArea >> 6) & MASK_6BITS];
+                   buffer[pos++] = encodeTable[bitWorkArea & MASK_6BITS];
+                   currentLinePos += BYTES_PER_ENCODED_BLOCK;
+                   if (lineLength > 0 && lineLength <= currentLinePos) {
+                       System.arraycopy(lineSeparator, 0, buffer, pos, lineSeparator.length);
+                       pos += lineSeparator.length;
+                       currentLinePos = 0;
+                   }
+               }
+           }
+       }
+   }
+
+   /**
+    * <p>
+    * Decodes all of the provided data, starting at inPos, for inAvail bytes. Should be called at least twice: once
+    * with the data to decode, and once with inAvail set to "-1" to alert decoder that EOF has been reached. The "-1"
+    * call is not necessary when decoding, but it doesn't hurt, either.
+    * </p>
+    * <p>
+    * Ignores all non-base64 characters. This is how chunked (e.g. 76 character) data is handled, since CR and LF are
+    * silently ignored, but has implications for other bytes, too. This method subscribes to the garbage-in,
+    * garbage-out philosophy: it will not check the provided data for validity.
+    * </p>
+    * <p>
+    * Thanks to "commons" project in ws.apache.org for the bitwise operations, and general approach.
+    * http://svn.apache.org/repos/asf/webservices/commons/trunk/modules/util/
+    * </p>
+    * 
+    * @param in
+    *            byte[] array of ascii data to base64 decode.
+    * @param inPos
+    *            Position to start reading data from.
+    * @param inAvail
+    *            Amount of bytes available from input for encoding.
+    */
+   void decode(byte[] in, int inPos, int inAvail) {
+       if (eof) {
+           return;
+       }
+       if (inAvail < 0) {
+           eof = true;
+       }
+       for (int i = 0; i < inAvail; i++) {
+           ensureBufferSize(decodeSize);
+           byte b = in[inPos++];
+           if (b == PAD) {
+               // We're done.
+               eof = true;
+               break;
+           } else {
+               if (b >= 0 && b < DECODE_TABLE.length) {
+                   int result = DECODE_TABLE[b];
+                   if (result >= 0) {
+                       modulus = (modulus+1) % BYTES_PER_ENCODED_BLOCK;
+                       bitWorkArea = (bitWorkArea << BITS_PER_ENCODED_BYTE) + result;
+                       if (modulus == 0) {
+                           buffer[pos++] = (byte) ((bitWorkArea >> 16) & MASK_8BITS);
+                           buffer[pos++] = (byte) ((bitWorkArea >> 8) & MASK_8BITS);
+                           buffer[pos++] = (byte) (bitWorkArea & MASK_8BITS);
+                       }
+                   }
+               }
+           }
+       }
+
+       // Two forms of EOF as far as base64 decoder is concerned: actual
+       // EOF (-1) and first time '=' character is encountered in stream.
+       // This approach makes the '=' padding characters completely optional.
+       if (eof && modulus != 0) {
+           ensureBufferSize(decodeSize);
+           
+           // We have some spare bits remaining
+           // Output all whole multiples of 8 bits and ignore the rest
+           switch (modulus) {
+          //   case 1: // 6 bits - ignore entirely
+          //       break;
+               case 2 : 
+                   bitWorkArea = bitWorkArea >> 4;
+                   buffer[pos++] = (byte) ((bitWorkArea) & MASK_8BITS);
+                   break;
+               case 3 :
+                   bitWorkArea = bitWorkArea >> 2; 
+                   buffer[pos++] = (byte) ((bitWorkArea >> 8) & MASK_8BITS);
+                   buffer[pos++] = (byte) ((bitWorkArea) & MASK_8BITS);
+				   break;
+			   default:
+				   break;
+           }
+       }
+   }
+   
+   /**
+    * Encodes binary data using the base64 algorithm but does not chunk the output.
+    * 
+    * @param binaryData
+    *            binary data to encode
+    * @return byte[] containing Base64 characters in their UTF-8 representation.
+    */
+   public static byte[] encodeBase64(byte[] binaryData) {
+       return encodeBase64(binaryData, false, false, Integer.MAX_VALUE);
+   }
+
+   /**
+    * Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.
+    * 
+    * @param binaryData
+    *            Array containing binary data to encode.
+    * @param isChunked
+    *            if <code>true</code> this encoder will chunk the base64 output into 76 character blocks
+    * @param urlSafe
+    *            if <code>true</code> this encoder will emit - and _ instead of the usual + and / characters.
+    * @param maxResultSize
+    *            The maximum result size to accept.
+    * @return Base64-encoded data.
+    * @throws IllegalArgumentException
+    *             Thrown when the input array needs an output array bigger than maxResultSize
+    * @since 1.4
+    */
+   public static byte[] encodeBase64(byte[] binaryData, boolean isChunked, boolean urlSafe, int maxResultSize) {
+       if (binaryData == null || binaryData.length == 0) {
+           return binaryData;
+       }
+
+       // Create this so can use the super-class method
+       // Also ensures that the same roundings are performed by the ctor and the code
+       Base64 b64 = isChunked ? new Base64(MIME_CHUNK_SIZE, CHUNK_SEPARATOR, urlSafe) : new Base64(0, CHUNK_SEPARATOR, urlSafe);
+       long len = b64.getEncodedLength(binaryData);
+       if (len > maxResultSize) {
+           throw new IllegalArgumentException("Input array too big, the output array would be bigger (" +
+               len +
+               ") than the specified maximum size of " +
+               maxResultSize);
+       }
+               
+       return b64.encode(binaryData);
+   }
+
+
+
+   /**
+    * Decodes Base64 data into octets
+    * 
+    * @param base64Data
+    *            Byte array containing Base64 data
+    * @return Array containing decoded data.
+    */
+   public static byte[] decodeBase64(byte[] base64Data) {
+       return new Base64().decode(base64Data);
+   }
+
+
+   /**
+    * Returns whether or not the <code>octet</code> is in the Base32 alphabet.
+    * 
+    * @param octet
+    *            The value to test
+    * @return <code>true</code> if the value is defined in the the Base32 alphabet <code>false</code> otherwise.
+    */
+   protected boolean isInAlphabet(byte octet) {
+       return octet >= 0 && octet < decodeTable.length && decodeTable[octet] != -1;
+   }
+
+   /**
+    * Below from base class
+    */
+
+   /**
+    *  MIME chunk size per RFC 2045 section 6.8.
+    *
+    * <p>
+    * The {@value} character limit does not count the trailing CRLF, but counts all other characters, including any
+    * equal signs.
+    * </p>
+    *
+    * @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045 section 6.8</a>
+    */
+   private static final int MIME_CHUNK_SIZE = 76;
+
+   private static final int DEFAULT_BUFFER_RESIZE_FACTOR = 2;
+
+   /**
+    * Defines the default buffer size - currently {@value}
+    * - must be large enough for at least one encoded block+separator
+    */
+   private static final int DEFAULT_BUFFER_SIZE = 8192;
+
+   /** Mask used to extract 8 bits, used in decoding bytes */
+   private static final int MASK_8BITS = 0xff;
+
+   /**
+    * Byte used to pad output.
+    */
+   private static final byte PAD_DEFAULT = '='; 
+
+   private static final byte PAD = PAD_DEFAULT; 
+
+   /** Number of bytes in each full block of unencoded data, e.g. 4 for Base64 and 5 for Base32 */
+   private final int unencodedBlockSize;
+
+   /** Number of bytes in each full block of encoded data, e.g. 3 for Base64 and 8 for Base32 */
+   private final int encodedBlockSize;
+
+   /**
+    * Chunksize for encoding. Not used when decoding.
+    * A value of zero or less implies no chunking of the encoded data.
+    * Rounded down to nearest multiple of encodedBlockSize.
+    */
+   private final int lineLength;
+
+   /**
+    * Size of chunk separator. Not used unless {@link #lineLength} > 0.
+    */
+   private final int chunkSeparatorLength;
+
+   /**
+    * Buffer for streaming.
+    */
+   private byte[] buffer;
+
+   /**
+    * Position where next character should be written in the buffer.
+    */
+   private int pos;
+
+   /**
+    * Position where next character should be read from the buffer.
+    */
+   private int readPos;
+
+   /**
+    * Boolean flag to indicate the EOF has been reached. Once EOF has been reached, this object becomes useless,
+    * and must be thrown away.
+    */
+   private boolean eof;
+
+   /**
+    * Variable tracks how many characters have been written to the current line. Only used when encoding. We use it to
+    * make sure each encoded line never goes beyond lineLength (if lineLength > 0).
+    */
+   private int currentLinePos;
+
+   /**
+    * Writes to the buffer only occur after every 3/5 reads when encoding, and every 4/8 reads when decoding.
+    * This variable helps track that.
+    */
+   private int modulus;
+
+   /**
+    * Ensure that the buffer has room for <code>size</code> bytes
+    *
+    * @param size minimum spare space required
+    */
+   private void ensureBufferSize(int size){
+       if ((buffer == null) || (buffer.length < pos + size)){
+           if (buffer == null) {
+               buffer = new byte[DEFAULT_BUFFER_SIZE];
+               pos = 0;
+               readPos = 0;
+           } else {
+               byte[] b = new byte[buffer.length * DEFAULT_BUFFER_RESIZE_FACTOR];
+               System.arraycopy(buffer, 0, b, 0, buffer.length);
+               buffer = b;
+           }
+       }
+   }
+
+   /**
+    * Extracts buffered data into the provided byte[] array, starting at position bPos,
+    * up to a maximum of bAvail bytes. Returns how many bytes were actually extracted.
+    *
+    * @param b
+    *            byte[] array to extract the buffered data into.
+    * @param bPos
+    *            position in byte[] array to start extraction at.
+    * @param bAvail
+    *            amount of bytes we're allowed to extract. We may extract fewer (if fewer are available).
+    * @return The number of bytes successfully extracted into the provided byte[] array.
+    */
+   private int readResults(byte[] b, int bPos, int bAvail) {
+       if (buffer != null) {
+           int len = Math.min(pos - readPos, bAvail);
+           System.arraycopy(buffer, readPos, b, bPos, len);
+           readPos += len;
+           if (readPos >= pos) {
+               buffer = null;
+           }
+           return len;
+       }
+       return eof ? -1 : 0;
+   }
+
+   /**
+    * Resets this object to its initial newly constructed state.
+    */
+   private void reset() {
+       buffer = null;
+       pos = 0;
+       readPos = 0;
+       currentLinePos = 0;
+       modulus = 0;
+       eof = false;
+   }
+
+   /**
+    * Decodes a byte[] containing characters in the Base-N alphabet.
+    *
+    * @param pArray
+    *            A byte array containing Base-N character data
+    * @return a byte array containing binary data
+    */
+   private byte[] decode(byte[] pArray) {
+       reset();
+       if (pArray == null || pArray.length == 0) {
+           return pArray;
+       }
+       decode(pArray, 0, pArray.length);
+       decode(pArray, 0, -1);
+       byte[] result = new byte[pos];
+       readResults(result, 0, result.length);
+       return result;
+   }
+
+   /**
+    * Encodes a byte[] containing binary data, into a byte[] containing characters in the alphabet.
+    *
+    * @param pArray
+    *            a byte array containing binary data
+    * @return A byte array containing only the basen alphabetic character data
+    */
+   private byte[] encode(byte[] pArray) {
+       reset();
+       if (pArray == null || pArray.length == 0) {
+           return pArray;
+       }
+       encode(pArray, 0, pArray.length);
+       encode(pArray, 0, -1); 
+       byte[] buf = new byte[pos - readPos];
+       readResults(buf, 0, buf.length);
+       return buf;
+   }
+
+   /**
+    * Tests a given byte array to see if it contains any characters within the alphabet or PAD.
+    *
+    * Intended for use in checking line-ending arrays
+    *
+    * @param arrayOctet
+    *            byte array to test
+    * @return <code>true</code> if any byte is a valid character in the alphabet or PAD; <code>false</code> otherwise
+    */
+   private boolean containsAlphabetOrPad(byte[] arrayOctet) {
+       if (arrayOctet == null) {
+           return false;
+       }
+       for (int i = 0; i < arrayOctet.length; i++) {
+           if (PAD == arrayOctet[i] || isInAlphabet(arrayOctet[i])) {
+               return true;
+           }
+       }
+       return false;
+   }
+
+   /**
+    * Calculates the amount of space needed to encode the supplied array.
+    *
+    * @param pArray byte[] array which will later be encoded
+    *
+    * @return amount of space needed to encoded the supplied array.
+    * Returns a long since a max-len array will require > Integer.MAX_VALUE
+    */
+   private long getEncodedLength(byte[] pArray) {
+       // Calculate non-chunked size - rounded up to allow for padding
+       // cast to long is needed to avoid possibility of overflow
+       long len = ((pArray.length + unencodedBlockSize-1)  / unencodedBlockSize) * (long) encodedBlockSize;
+       if (lineLength > 0) { 
+			/**
+			 * Round up to nearest multiple
+			 */
+           len += ((len + lineLength-1) / lineLength) * chunkSeparatorLength;
+       }
+       return len;
+   }
+}

client/src/main/java/com/alibaba/nacos/client/identify/Constants.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.identify;
+
+/**
+ * Identify Constants
+ * 
+ * @author Nacos
+ *
+ */
+public class Constants {
+	public static final String ACCESS_KEY = "accessKey";
+	
+	public static final String SECRET_KEY = "secretKey";
+	
+	public static final String PROPERTIES_FILENAME = "spas.properties";
+
+    public static final String CREDENTIAL_PATH = "/home/admin/.spas_key/";
+
+    public static final String CREDENTIAL_DEFAULT = "default";
+
+    public static final String DOCKER_CREDENTIAL_PATH = "/etc/instanceInfo";
+
+    public static final String DOCKER_ACCESS_KEY = "env_spas_accessKey";
+
+    public static final String DOCKER_SECRET_KEY = "env_spas_secretKey";
+
+    public static final String ENV_ACCESS_KEY = "spas_accessKey";
+
+    public static final String ENV_SECRET_KEY = "spas_secretKey";
+
+    public static final String NO_APP_NAME = "";
+
+}

client/src/main/java/com/alibaba/nacos/client/identify/CredentialListener.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.identify;
+
+/**
+ * Credential Listener
+ * 
+ * @author Nacos
+ *
+ */
+public interface CredentialListener {
+	/**
+	 * update Credential
+	 */
+    public void onUpdateCredential();
+}

client/src/main/java/com/alibaba/nacos/client/identify/CredentialService.java

@@ -0,0 +1,135 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.identify;
+
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Credential Service
+ * 
+ * @author Nacos
+ *
+ */
+public final class CredentialService implements SpasCredentialLoader {
+	static final public Logger log = LogUtils.logger(CredentialService.class);
+    private static ConcurrentHashMap<String, CredentialService> instances = new ConcurrentHashMap<String, CredentialService>();
+
+    private String appName;
+	private Credentials credentials = new Credentials();
+    private CredentialWatcher watcher;
+    private CredentialListener listener;
+	
+	private CredentialService(String appName) {
+        if (appName == null) {
+        	String value = System.getProperty("project.name");
+        	if (StringUtils.isNotEmpty(value)) {
+				appName = value;
+			}
+        }
+        this.appName = appName;
+        watcher = new CredentialWatcher(appName, this);
+	}
+	
+	
+	public static CredentialService getInstance() {
+        return getInstance(null);
+	}
+
+    public static CredentialService getInstance(String appName) {
+        String key = appName != null ? appName : Constants.NO_APP_NAME;
+        CredentialService instance = instances.get(key);
+        if (instance == null) {
+            instance = new CredentialService(appName);
+            CredentialService previous = instances.putIfAbsent(key, instance);
+            if (previous != null) {
+                instance = previous;
+            }
+        }
+        return instance;
+    }
+
+    public static CredentialService freeInstance() {
+        return freeInstance(null);
+    }
+
+    public static CredentialService freeInstance(String appName) {
+        String key = appName != null ? appName : Constants.NO_APP_NAME;
+        CredentialService instance = instances.remove(key);
+        if (instance != null) {
+            instance.free();
+        }
+        return instance;
+    }
+
+    public void free() {
+        if (watcher != null) {
+            watcher.stop();
+        }
+        log.info(appName, this.getClass().getSimpleName() + " is freed");
+    }
+
+	public Credentials getCredential() {
+        Credentials localCredential = credentials;
+        if (localCredential.valid()) {
+            return localCredential;
+        }
+		return credentials;
+	}
+
+    public void setCredential(Credentials credential) {
+        boolean changed = !(credentials == credential || (credentials != null && credentials.identical(credential)));
+        credentials = credential;
+        if (changed && listener != null) {
+            listener.onUpdateCredential();
+        }
+    }
+
+    public void setStaticCredential(Credentials credential) {
+        if (watcher != null) {
+            watcher.stop();
+        }
+        setCredential(credential);
+    }
+
+    public void registerCredentialListener(CredentialListener listener) {
+        this.listener = listener;
+    }
+
+    @Deprecated
+	public void setAccessKey(String accessKey) {
+		credentials.setAccessKey(accessKey);
+	}
+
+    @Deprecated
+	public void setSecretKey(String secretKey) {
+		credentials.setSecretKey(secretKey);
+	}
+
+    @Deprecated
+	public String getAccessKey() {
+		return credentials.getAccessKey();
+	}
+
+    @Deprecated
+	public String getSecretKey() {
+		return credentials.getSecretKey();
+	}
+
+}

client/src/main/java/com/alibaba/nacos/client/identify/CredentialWatcher.java

@@ -0,0 +1,214 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.identify;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.util.Properties;
+import java.util.Timer;
+import java.util.TimerTask;
+
+import com.alibaba.nacos.client.config.utils.LogUtils;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.utils.StringUtils;
+
+/**
+ * Credential Watcher
+ * 
+ * @author Nacos
+ *
+ */
+public class CredentialWatcher {
+	static final public Logger SpasLogger = LogUtils.logger(CredentialWatcher.class);
+    private static final long REFRESH_INTERVAL = 10 * 1000;
+
+    private CredentialService serviceInstance;
+    private String appName;
+    private String propertyPath;
+    private TimerTask watcher;
+    private boolean stopped;
+
+    @SuppressWarnings("PMD.AvoidUseTimerRule")
+    public CredentialWatcher(String appName, CredentialService serviceInstance) {
+        this.appName = appName;
+        this.serviceInstance = serviceInstance;
+        loadCredential(true);
+        watcher = new TimerTask() {
+            private Timer timer = new Timer(true);
+            private long modified = 0;
+
+            {
+                timer.schedule(this, REFRESH_INTERVAL, REFRESH_INTERVAL);
+            }
+
+            @Override
+            public void run() {
+                synchronized (this) {
+                    if (stopped) {
+                        return;
+                    }
+                    boolean reload = false;
+                    if (propertyPath == null) {
+                        reload = true;
+                    } else {
+                        File file = new File(propertyPath);
+                        long lastModified = file.lastModified();
+                        if (modified != lastModified) {
+                            reload = true;
+                            modified = lastModified;
+                        }
+                    }
+                    if (reload) {
+                        loadCredential(false);
+                    }
+                }
+            }
+        };
+    }
+
+    public void stop() {
+        if (stopped) {
+            return;
+        }
+        if (watcher != null) {
+            synchronized (watcher) {
+                watcher.cancel();
+                stopped = true;
+            }
+        }
+        SpasLogger.info(appName, this.getClass().getSimpleName() + " is stopped");
+    }
+
+    private void loadCredential(boolean init) {
+        boolean logWarn = init;
+        if (propertyPath == null) {
+            URL url = ClassLoader.getSystemResource(Constants.PROPERTIES_FILENAME);
+            if (url != null) {
+                propertyPath = url.getPath();
+            }
+            if (propertyPath == null || propertyPath.isEmpty()) {
+            	
+            	String value = System.getProperty("spas.identity");
+				if (StringUtils.isNotEmpty(value)) {
+					propertyPath = value;
+				}
+                if (propertyPath == null || propertyPath.isEmpty()) {
+                    propertyPath = Constants.CREDENTIAL_PATH + (appName == null ? Constants.CREDENTIAL_DEFAULT : appName);
+                }
+                else {
+                    if (logWarn) {
+                        SpasLogger.info(appName, "Defined credential file: -D" + "spas.identity" + "=" + propertyPath);
+                    }
+                }
+            }
+            else {
+                if (logWarn) {
+                    SpasLogger.info(appName, "Load credential file from classpath: " + Constants.PROPERTIES_FILENAME);
+                }
+            }
+        }
+
+        InputStream propertiesIS = null;
+        do {
+            try {
+                propertiesIS = new FileInputStream(propertyPath);
+            } catch (FileNotFoundException e) {
+                if (appName != null && !appName.equals(Constants.CREDENTIAL_DEFAULT) && propertyPath.equals(Constants.CREDENTIAL_PATH + appName)) {
+                    propertyPath = Constants.CREDENTIAL_PATH + Constants.CREDENTIAL_DEFAULT;
+                    continue;
+                }
+                if (!Constants.DOCKER_CREDENTIAL_PATH.equals(propertyPath)) {
+                    propertyPath = Constants.DOCKER_CREDENTIAL_PATH;
+                    continue;
+                }
+            }
+            break;
+        } while (true);
+
+        String accessKey = null;
+        String secretKey = null;
+        if (propertiesIS == null) {
+            propertyPath = null;
+            accessKey = System.getenv(Constants.ENV_ACCESS_KEY);
+            secretKey = System.getenv(Constants.ENV_SECRET_KEY);
+            if (accessKey == null && secretKey == null) {
+                if (logWarn) {
+                    SpasLogger.info(appName, "No credential found");
+                }
+                return;
+            }
+        }
+        else {
+            Properties properties = new Properties();
+            try {
+                properties.load(propertiesIS);
+            } catch (IOException e) {
+				SpasLogger.error("26", "Unable to load credential file, appName:" + appName
+						+ "Unable to load credential file " + propertyPath, e);
+				propertyPath = null;
+                return;
+            } finally {
+                try {
+                    propertiesIS.close();
+                } catch (IOException e) {
+                	SpasLogger.error("27", "Unable to close credential file, appName:" + appName
+    						+ "Unable to close credential file " + propertyPath, e);
+                }
+            }
+
+            if (logWarn) {
+                SpasLogger.info(appName, "Load credential file " + propertyPath);
+            }
+
+            if (!Constants.DOCKER_CREDENTIAL_PATH.equals(propertyPath)) {
+                if (properties.containsKey(Constants.ACCESS_KEY)) {
+                    accessKey = properties.getProperty(Constants.ACCESS_KEY);
+                }
+                if (properties.containsKey(Constants.SECRET_KEY)) {
+                    secretKey = properties.getProperty(Constants.SECRET_KEY);
+                }
+            } else {
+                if (properties.containsKey(Constants.DOCKER_ACCESS_KEY)) {
+                    accessKey = properties.getProperty(Constants.DOCKER_ACCESS_KEY);
+                }
+                if (properties.containsKey(Constants.DOCKER_SECRET_KEY)) {
+                    secretKey = properties.getProperty(Constants.DOCKER_SECRET_KEY);
+                }
+            }
+        }
+
+        if (accessKey != null) {
+            accessKey = accessKey.trim();
+        }
+        if (secretKey != null) {
+            secretKey = secretKey.trim();
+        }
+
+        Credentials credential = new Credentials(accessKey, secretKey);
+		if (!credential.valid()) {
+			SpasLogger.warn("1", "Credential file missing required property" + appName + "Credential file missing "
+					+ Constants.ACCESS_KEY + " or " + Constants.SECRET_KEY);
+			propertyPath = null;
+			// return;
+		}
+
+        serviceInstance.setCredential(credential);
+    }
+}

client/src/main/java/com/alibaba/nacos/client/identify/Credentials.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.identify;
+
+/**
+ * Credentials
+ * 
+ * @author Nacos
+ *
+ */
+public class Credentials implements SpasCredential {
+	
+	private volatile String accessKey;
+	
+	private volatile String secretKey;
+	
+	public Credentials(String accessKey, String secretKey) {
+		this.accessKey = accessKey;
+		this.secretKey = secretKey;
+	}
+	
+	public Credentials() {
+		this(null, null);
+	}
+	
+	public String getAccessKey() {
+		return accessKey;
+	}
+
+	public void setAccessKey(String accessKey) {
+		this.accessKey = accessKey;
+	}
+
+	public String getSecretKey() {
+		return secretKey;
+	}
+
+	public void setSecretKey(String secretKey) {
+		this.secretKey = secretKey;
+	}
+
+    public boolean valid() {
+        return accessKey != null && !accessKey.isEmpty() && secretKey != null && !secretKey.isEmpty();
+    }
+
+    public boolean identical(Credentials other) {
+        return this == other ||
+               (other != null &&
+                (accessKey == null && other.accessKey == null || accessKey != null && accessKey.equals(other.accessKey)) &&
+                (secretKey == null && other.secretKey == null || secretKey != null && secretKey.equals(other.secretKey)));
+    }
+}

client/src/main/java/com/alibaba/nacos/client/identify/STSConfig.java

@@ -0,0 +1,128 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.identify;
+
+import com.alibaba.nacos.client.utils.StringUtils;
+
+/**
+ * Sts config
+ * 
+ * @author Nacos
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public class STSConfig {
+	private static final String RAM_SECURITY_CREDENTIALS_URL
+		= "";
+	private String ramRoleName;
+	/**
+	 * STS 临时凭证有效期剩余多少时开始刷新（允许本地时间比 STS 服务时间最多慢多久）
+	 */
+	private int timeToRefreshInMillisecond = 3 * 60 * 1000;
+	/**
+	 * 获取 STS 临时凭证的元数据接口（包含角色名称）
+	 */
+	private String securityCredentialsUrl;
+	/**
+	 * 设定 STS 临时凭证，不再通过元数据接口获取
+	 */
+	private String securityCredentials;
+	/**
+	 * 是否缓存
+	 */
+	private boolean cacheSecurityCredentials = true;
+
+	private static class Singleton {
+		private static final STSConfig INSTANCE = new STSConfig();
+	}
+
+	private STSConfig() {
+		String ramRoleName = System.getProperty("ram.role.name");
+		if (!StringUtils.isBlank(ramRoleName)) {
+			setRamRoleName(ramRoleName);
+		}
+
+		String timeToRefreshInMillisecond = System.getProperty("time.to.refresh.in.millisecond");
+		if (!StringUtils.isBlank(timeToRefreshInMillisecond)) {
+			setTimeToRefreshInMillisecond(Integer.parseInt(timeToRefreshInMillisecond));
+		}
+
+		String securityCredentials = System.getProperty("security.credentials");
+		if (!StringUtils.isBlank(securityCredentials)) {
+			setSecurityCredentials(securityCredentials);
+		}
+
+		String securityCredentialsUrl = System.getProperty("security.credentials.url");
+		if (!StringUtils.isBlank(securityCredentialsUrl)) {
+			setSecurityCredentialsUrl(securityCredentialsUrl);
+		}
+
+		String cacheSecurityCredentials = System.getProperty("cache.security.credentials");
+		if (!StringUtils.isBlank(cacheSecurityCredentials)) {
+			setCacheSecurityCredentials(Boolean.valueOf(cacheSecurityCredentials));
+		}
+	}
+
+	public static STSConfig getInstance() {
+		return Singleton.INSTANCE;
+	}
+
+	public String getRamRoleName() {
+		return ramRoleName;
+	}
+
+	public void setRamRoleName(String ramRoleName) {
+		this.ramRoleName = ramRoleName;
+	}
+
+	public int getTimeToRefreshInMillisecond() {
+		return timeToRefreshInMillisecond;
+	}
+
+	public void setTimeToRefreshInMillisecond(int timeToRefreshInMillisecond) {
+		this.timeToRefreshInMillisecond = timeToRefreshInMillisecond;
+	}
+
+	public String getSecurityCredentialsUrl() {
+		if (securityCredentialsUrl == null && ramRoleName != null) {
+			return RAM_SECURITY_CREDENTIALS_URL + ramRoleName;
+		}
+		return securityCredentialsUrl;
+	}
+
+	public void setSecurityCredentialsUrl(String securityCredentialsUrl) {
+		this.securityCredentialsUrl = securityCredentialsUrl;
+	}
+
+	public String getSecurityCredentials() {
+		return securityCredentials;
+	}
+
+	public void setSecurityCredentials(String securityCredentials) {
+		this.securityCredentials = securityCredentials;
+	}
+
+	public boolean isSTSOn() {
+		return StringUtils.isNotEmpty(getSecurityCredentials()) || StringUtils.isNotEmpty(getSecurityCredentialsUrl());
+	}
+
+	public boolean isCacheSecurityCredentials() {
+		return cacheSecurityCredentials;
+	}
+
+	public void setCacheSecurityCredentials(boolean cacheSecurityCredentials) {
+		this.cacheSecurityCredentials = cacheSecurityCredentials;
+	}
+}

client/src/main/java/com/alibaba/nacos/client/identify/SpasCredential.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.identify;
+
+/**
+ * Spas Credential Interface
+ * 
+ * @author Nacos
+ *
+ */
+public interface SpasCredential {
+	/**
+	 * get AccessKey
+	 * 
+	 * @return AccessKey
+	 */
+	public String getAccessKey();
+
+	/**
+	 * get SecretKey
+	 * 
+	 * @return SecretKey
+	 */
+	public String getSecretKey();
+}

client/src/main/java/com/alibaba/nacos/client/identify/SpasCredentialLoader.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.identify;
+
+/**
+ * Spas Credential Loader
+ * 
+ * @author Nacos
+ *
+ */
+public interface SpasCredentialLoader {
+	/**
+	 * get Credential
+	 * 
+	 * @return Credential
+	 */
+    SpasCredential getCredential();
+}

client/src/main/java/com/alibaba/nacos/client/logger/Level.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger;
+
+/**
+ * 阿里中间件日志级别
+ * 
+ * @author zhuyong 2014年3月20日 上午9:57:27
+ */
+public enum Level {
+	/**
+	 * log level
+	 */
+    DEBUG("DEBUG"), INFO("INFO"), WARN("WARN"), ERROR("ERROR"), OFF("OFF");
+
+    private String name;
+
+    Level(String name) {
+        this.name = name;
+    }
+
+    public String getName() {
+        return this.name;
+    }
+
+    public static Level codeOf(String level) {
+        for (Level l : Level.values()) {
+            if (l.name.equals(level)) {
+                return l;
+            }
+        }
+
+        return OFF;
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/Logger.java

@@ -0,0 +1,238 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger;
+
+import com.alibaba.nacos.client.logger.option.ActivateOption;
+
+/**
+ * <pre>
+ * 阿里中间件日志API，用于输出定制化的日志
+ * 
+ * 定制格式如下：01 %d{yyyy-MM-dd HH:mm:ss.SSS} %p [%-5t:%c{2}] %m%n
+ * 其中：
+ * 01                           日志API版本，后续如果格式有变化，会修改此版本号，方便机器解析
+ * d{yyyy-MM-dd HH:mm:ss.SSS}   时间，如，2014-03-19 20:55:08.501，最后面的表示毫秒
+ * %p                           日志级别，如INFO,ERROR
+ * [%-5t:%c{2}]                 线程名:日志名
+ * %m                           日志信息
+ * %n                           换行
+ * 
+ * 关于%m，也有其中的格式要求：[Context] [STAT-INFO] [ERROR-CODE]
+ * 其中：
+ * Context                      打印时间时的上下文信息，如果没有，则内容为空，但'[]'这个占位符仍要输出
+ * STAT-INFO                    待定
+ * ERROR-CODE                   常见的错误码，帮助用户解决问题
+ * 
+ * 在异常中，也需要输出ErrorCode及对应的TraceUrl，可以使用
+ * com.alibaba.nacos.client.logger.support.LoggerHelper.getErrorCodeStr(String errorCode)来获取格式化后的串
+ * </pre>
+ * 
+ * @author zhuyong 2014年3月20日 上午9:58:27
+ */
+public interface Logger extends ActivateOption {
+
+    /**
+     * 输出Debug日志
+     *
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     */
+    void debug(String message);
+
+    /**
+     * 输出Debug日志
+     *
+     * @param format 日志信息格式化字符串，比如 'Hi,{} {} {}'（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param args 格式化串参数数组
+     */
+    void debug(String format, Object... args);
+
+    /**
+     * 输出Debug日志
+     *
+     * @param context 日志上下文信息
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     */
+    void debug(String context, String message);
+
+    /**
+     * 输出Debug日志
+     *
+     * @param context 日志上下文信息
+     * @param format 日志信息格式化字符串，比如 'Hi,{} {} {}'（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param args 格式化串参数数组
+     */
+    void debug(String context, String format, Object... args);
+
+    /**
+     * 输出Info日志
+     *
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     */
+    void info(String message);
+
+    /**
+     * 输出Info日志
+     *
+     * @param format 日志信息格式化字符串，比如 'Hi,{} {} {}'（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param args 格式化串参数数组
+     */
+    void info(String format, Object... args);
+
+    /**
+     * 输出Info日志
+     *
+     * @param context 日志上下文信息
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     */
+    void info(String context, String message);
+
+    /**
+     * 输出Info日志
+     *
+     * @param context 日志上下文信息
+     * @param format 日志信息格式化字符串，比如 'Hi,{} {} {}'（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param args 格式化串参数数组
+     */
+    void info(String context, String format, Object... args);
+
+    /**
+     * 输出Warn日志
+     *
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     */
+    void warn(String message);
+
+    /**
+     * 输出Warn日志
+     *
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param t 异常信息
+     * @since 0.1.5
+     */
+    void warn(String message, Throwable t);
+
+    /**
+     * 输出Warn日志
+     *
+     * @param format 日志信息格式化字符串，比如 'Hi,{} {} {}'（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param args 格式化串参数数组
+     */
+    void warn(String format, Object... args);
+
+    /**
+     * 输出Warn日志
+     *
+     * @param context 日志上下文信息
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     */
+    void warn(String context, String message);
+
+    /**
+     * 输出Warn日志
+     *
+     * @param context 日志上下文信息
+     * @param format 日志信息格式化字符串，比如 'Hi,{} {} {}'（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param args 格式化串参数数组
+     */
+    void warn(String context, String format, Object... args);
+
+    /**
+     * 输出Error日志
+     *
+     * @param errorCode 错误码，如HSF-0001
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     */
+    void error(String errorCode, String message);
+
+    /**
+     * 输出Error日志
+     *
+     * @param errorCode 错误码，如HSF-0001
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param t 异常信息
+     */
+    void error(String errorCode, String message, Throwable t);
+
+    /**
+     * 输出Error日志
+     *
+     * @param errorCode 错误码，如HSF-0001
+     * @param format 日志信息格式化字符串，比如 'Hi,{} {} {}'（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param objs 格式化串参数数组
+     */
+    void error(String errorCode, String format, Object... objs);
+
+    /**
+     * 输出Error日志
+     *
+     * @param context 日志上下文信息
+     * @param errorCode 错误码
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     */
+    void error(String context, String errorCode, String message);
+
+    /**
+     * 输出Error日志
+     *
+     * @param context 日志上下文信息
+     * @param errorCode 错误码
+     * @param message 日志信息（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param t 异常信息
+     */
+    void error(String context, String errorCode, String message, Throwable t);
+
+    /**
+     * 输出Error日志
+     *
+     * @param context 日志上下文信息
+     * @param errorCode 错误码
+     * @param format 日志信息格式化字符串，比如 'Hi,{} {} {}'（当使用ResourceBundle用于国际化日志输出时，message为对应的key, since 0.1.5）
+     * @param args 格式化串参数
+     */
+    void error(String context, String errorCode, String format, Object... args);
+
+	/**
+	 * 判断Debug级别是否开启
+	 * 
+	 * @return Debug级别是否开启
+	 */
+    boolean isDebugEnabled();
+
+    /**
+     * 判断Info级别是否开启
+     * @return Info级别是否开启
+     */
+    boolean isInfoEnabled();
+
+    /**
+     * 判断Warn级别是否开启
+     * @return Warn级别是否开启
+     */
+    boolean isWarnEnabled();
+
+	/**
+	 * 判断Error级别是否开启
+	 * 
+	 * @return Error级别是否开启
+	 */
+    boolean isErrorEnabled();
+
+    /**
+     * * 获取内部日志实现对象
+     * @return 内部日志实现对象
+     */
+    Object getDelegate();
+}

client/src/main/java/com/alibaba/nacos/client/logger/LoggerFactory.java

@@ -0,0 +1,100 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import com.alibaba.nacos.client.logger.log4j.Log4jLoggerFactory;
+import com.alibaba.nacos.client.logger.log4j2.Log4j2LoggerFactory;
+import com.alibaba.nacos.client.logger.nop.NopLoggerFactory;
+import com.alibaba.nacos.client.logger.slf4j.Slf4jLoggerFactory;
+import com.alibaba.nacos.client.logger.support.ILoggerFactory;
+import com.alibaba.nacos.client.logger.support.LogLog;
+
+/**
+ * <pre>
+ * 阿里中间件LoggerFactory，获取具体日志实现
+ * 目前支持log4j/log4j2/slf4j/jcl日志门面和log4j/log4j2/logback日志实现：
+ * log4j
+ * log4j2
+ * slf4j + logback
+ * slf4j + slf4j-log4j12 + log4j
+ * slf4j + slf4j-log4j-impl + log4j2
+ * jcl + log4j
+ * jcl + jcl-over-slf4j + slf4j + logback
+ * jcl + jcl-over-slf4j + slf4j + slf4j-log4j-impl + log4j
+ * 查找实现的优先顺序依次为slf4j > log4j > log4j2
+ * </pre>
+ *
+ * @author zhuyong 2014年3月20日 上午10:17:33
+ */
+public class LoggerFactory {
+
+    private LoggerFactory() {
+    }
+
+    private static volatile ILoggerFactory LOGGER_FACTORY;
+    private static Map<String, Logger> loggerCache;
+
+    // 查找常用的日志框架
+    static {
+        try {
+            setLoggerFactory(new Slf4jLoggerFactory());
+            LogLog.info("Init JM logger with Slf4jLoggerFactory success, " + LoggerFactory.class.getClassLoader());
+        } catch (Throwable e1) {
+            try {
+                setLoggerFactory(new Log4jLoggerFactory());
+                LogLog.info("Init JM logger with Log4jLoggerFactory, " + LoggerFactory.class.getClassLoader());
+            } catch (Throwable e2) {
+                try {
+                    setLoggerFactory(new Log4j2LoggerFactory());
+                    LogLog.info("Init JM logger with Log4j2LoggerFactory, " + LoggerFactory.class.getClassLoader());
+                } catch (Throwable e3) {
+                    setLoggerFactory(new NopLoggerFactory());
+                    LogLog.warn("Init JM logger with NopLoggerFactory, pay attention. "
+                                + LoggerFactory.class.getClassLoader(), e2);
+                }
+            }
+        }
+
+        loggerCache = new ConcurrentHashMap<String, Logger>();
+    }
+
+    public static Logger getLogger(String name) {
+        Logger logger = loggerCache.get(name);
+        if (logger == null) {
+            synchronized (LOGGER_FACTORY) {
+                logger = loggerCache.get(name);
+                if (logger == null) {
+                    logger = LOGGER_FACTORY.getLogger(name);
+                    loggerCache.put(name, logger);
+                }
+            }
+        }
+        return logger;
+    }
+
+    public static Logger getLogger(Class<?> clazz) {
+        return getLogger(clazz.getName());
+    }
+
+    private static void setLoggerFactory(ILoggerFactory loggerFactory) {
+        if (loggerFactory != null) {
+            LoggerFactory.LOGGER_FACTORY = loggerFactory;
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/JSONArray.java

@@ -0,0 +1,398 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * $Id: JSONArray.java,v 1.1 2006/04/15 14:10:48 platform Exp $
+ * Created on 2006-4-10
+ */
+package com.alibaba.nacos.client.logger.json;
+
+import java.io.IOException;
+import java.io.StringWriter;
+import java.io.Writer;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Iterator;
+
+/**
+ * A JSON array. JSONObject supports java.util.List interface.
+ * 
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public class JSONArray extends ArrayList implements JSONAware, JSONStreamAware {
+	private static final long serialVersionUID = 3957988303675231981L;
+	
+	/**
+	 * Constructs an empty JSONArray.
+	 */
+	public JSONArray(){
+		super();
+	}
+	
+	/**
+	 * Constructs a JSONArray containing the elements of the specified
+	 * collection, in the order they are returned by the collection's iterator.
+	 * 
+	 * @param c the collection whose elements are to be placed into this JSONArray
+	 */
+	public JSONArray(Collection c){
+		super(c);
+	}
+	
+    /**
+     * Encode a list into JSON text and write it to out. 
+     * If this list is also a JSONStreamAware or a JSONAware, JSONStreamAware and JSONAware specific behaviours will be ignored at this top level.
+     * 
+     * @see com.alibaba.nacos.client.logger.json.JSONValue#writeJSONString(Object, Writer)
+     * 
+     * @param collection
+     * @param out
+     */
+	public static void writeJSONString(Collection collection, Writer out) throws IOException{
+		if(collection == null){
+			out.write("null");
+			return;
+		}
+		
+		boolean first = true;
+		Iterator iter=collection.iterator();
+		
+        out.write('[');
+		while(iter.hasNext()){
+            if(first) {
+                first = false;
+            }
+            else {
+                out.write(',');
+            }
+			Object value=iter.next();
+			if(value == null){
+				out.write("null");
+				continue;
+			}
+			
+			JSONValue.writeJSONString(value, out);
+		}
+		out.write(']');
+	}
+	
+	public void writeJSONString(Writer out) throws IOException{
+		writeJSONString(this, out);
+	}
+	
+	/**
+	 * Convert a list to JSON text. The result is a JSON array. 
+	 * If this list is also a JSONAware, JSONAware specific behaviours will be omitted at this top level.
+	 * 
+	 * @see com.alibaba.nacos.client.logger.json.JSONValue#toJSONString(Object)
+	 * 
+	 * @param collection
+	 * @return JSON text, or "null" if list is null.
+	 */
+	public static String toJSONString(Collection collection){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(collection, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+
+	public static void writeJSONString(byte[] array, Writer out) throws IOException{
+		if(array == null){
+			out.write("null");
+		} else if(array.length == 0) {
+			out.write("[]");
+		} else {
+			out.write("[");
+			out.write(String.valueOf(array[0]));
+			
+			for(int i = 1; i < array.length; i++){
+				out.write(",");
+				out.write(String.valueOf(array[i]));
+			}
+			
+			out.write("]");
+		}
+	}
+	
+	public static String toJSONString(byte[] array){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(array, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public static void writeJSONString(short[] array, Writer out) throws IOException{
+		if(array == null){
+			out.write("null");
+		} else if(array.length == 0) {
+			out.write("[]");
+		} else {
+			out.write("[");
+			out.write(String.valueOf(array[0]));
+			
+			for(int i = 1; i < array.length; i++){
+				out.write(",");
+				out.write(String.valueOf(array[i]));
+			}
+			
+			out.write("]");
+		}
+	}
+	
+	public static String toJSONString(short[] array){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(array, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public static void writeJSONString(int[] array, Writer out) throws IOException{
+		if(array == null){
+			out.write("null");
+		} else if(array.length == 0) {
+			out.write("[]");
+		} else {
+			out.write("[");
+			out.write(String.valueOf(array[0]));
+			
+			for(int i = 1; i < array.length; i++){
+				out.write(",");
+				out.write(String.valueOf(array[i]));
+			}
+			
+			out.write("]");
+		}
+	}
+	
+	public static String toJSONString(int[] array){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(array, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public static void writeJSONString(long[] array, Writer out) throws IOException{
+		if(array == null){
+			out.write("null");
+		} else if(array.length == 0) {
+			out.write("[]");
+		} else {
+			out.write("[");
+			out.write(String.valueOf(array[0]));
+			
+			for(int i = 1; i < array.length; i++){
+				out.write(",");
+				out.write(String.valueOf(array[i]));
+			}
+			
+			out.write("]");
+		}
+	}
+	
+	public static String toJSONString(long[] array){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(array, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public static void writeJSONString(float[] array, Writer out) throws IOException{
+		if(array == null){
+			out.write("null");
+		} else if(array.length == 0) {
+			out.write("[]");
+		} else {
+			out.write("[");
+			out.write(String.valueOf(array[0]));
+			
+			for(int i = 1; i < array.length; i++){
+				out.write(",");
+				out.write(String.valueOf(array[i]));
+			}
+			
+			out.write("]");
+		}
+	}
+	
+	public static String toJSONString(float[] array){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(array, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public static void writeJSONString(double[] array, Writer out) throws IOException{
+		if(array == null){
+			out.write("null");
+		} else if(array.length == 0) {
+			out.write("[]");
+		} else {
+			out.write("[");
+			out.write(String.valueOf(array[0]));
+			
+			for(int i = 1; i < array.length; i++){
+				out.write(",");
+				out.write(String.valueOf(array[i]));
+			}
+			
+			out.write("]");
+		}
+	}
+	
+	public static String toJSONString(double[] array){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(array, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public static void writeJSONString(boolean[] array, Writer out) throws IOException{
+		if(array == null){
+			out.write("null");
+		} else if(array.length == 0) {
+			out.write("[]");
+		} else {
+			out.write("[");
+			out.write(String.valueOf(array[0]));
+			
+			for(int i = 1; i < array.length; i++){
+				out.write(",");
+				out.write(String.valueOf(array[i]));
+			}
+			
+			out.write("]");
+		}
+	}
+	
+	public static String toJSONString(boolean[] array){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(array, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public static void writeJSONString(char[] array, Writer out) throws IOException{
+		if(array == null){
+			out.write("null");
+		} else if(array.length == 0) {
+			out.write("[]");
+		} else {
+			out.write("[\"");
+			out.write(String.valueOf(array[0]));
+			
+			for(int i = 1; i < array.length; i++){
+				out.write("\",\"");
+				out.write(String.valueOf(array[i]));
+			}
+			
+			out.write("\"]");
+		}
+	}
+	
+	public static String toJSONString(char[] array){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(array, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public static void writeJSONString(Object[] array, Writer out) throws IOException{
+		if(array == null){
+			out.write("null");
+		} else if(array.length == 0) {
+			out.write("[]");
+		} else {
+			out.write("[");
+			JSONValue.writeJSONString(array[0], out);
+			
+			for(int i = 1; i < array.length; i++){
+				out.write(",");
+				JSONValue.writeJSONString(array[i], out);
+			}
+			
+			out.write("]");
+		}
+	}
+	
+	public static String toJSONString(Object[] array){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(array, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public String toJSONString(){
+		return toJSONString(this);
+	}
+
+	/**
+	 * Returns a string representation of this array. This is equivalent to
+	 * calling {@link JSONArray#toJSONString()}.
+	 */
+	public String toString() {
+		return toJSONString();
+	}
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/JSONAware.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.json;
+
+/**
+ * Beans that support customized output of JSON text shall implement this interface.  
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public interface JSONAware {
+	/**
+	 * format change
+	 * 
+	 * @return JSON text
+	 */
+	String toJSONString();
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/JSONObject.java

@@ -0,0 +1,152 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * $Id: JSONObject.java,v 1.1 2006/04/15 14:10:48 platform Exp $
+ * Created on 2006-4-10
+ */
+package com.alibaba.nacos.client.logger.json;
+
+import java.io.IOException;
+import java.io.StringWriter;
+import java.io.Writer;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+
+/**
+ * A JSON object. Key value pairs are unordered. JSONObject supports java.util.Map interface.
+ * 
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public class JSONObject extends HashMap implements Map, JSONAware, JSONStreamAware{
+	
+	private static final long serialVersionUID = -503443796854799292L;
+	
+	
+	public JSONObject() {
+		super();
+	}
+
+	/**
+	 * Allows creation of a JSONObject from a Map. After that, both the
+	 * generated JSONObject and the Map can be modified independently.
+	 * 
+	 * @param map
+	 */
+	public JSONObject(Map map) {
+		super(map);
+	}
+
+
+    /**
+     * Encode a map into JSON text and write it to out.
+     * If this map is also a JSONAware or JSONStreamAware, JSONAware or JSONStreamAware specific behaviours will be ignored at this top level.
+     * 
+     * @see com.alibaba.nacos.client.logger.json.JSONValue#writeJSONString(Object, Writer)
+     * 
+     * @param map
+     * @param out
+     */
+	public static void writeJSONString(Map map, Writer out) throws IOException {
+		if(map == null){
+			out.write("null");
+			return;
+		}
+		
+		boolean first = true;
+		Iterator iter=map.entrySet().iterator();
+		
+        out.write('{');
+		while(iter.hasNext()){
+			if (first) {
+				first = false;
+			}
+			else {
+				out.write(',');
+			}
+			Map.Entry entry = (Map.Entry) iter.next();
+            out.write('\"');
+            out.write(escape(String.valueOf(entry.getKey())));
+            out.write('\"');
+            out.write(':');
+			JSONValue.writeJSONString(entry.getValue(), out);
+		}
+		out.write('}');
+	}
+
+	public void writeJSONString(Writer out) throws IOException{
+		writeJSONString(this, out);
+	}
+	
+	/**
+	 * Convert a map to JSON text. The result is a JSON object. 
+	 * If this map is also a JSONAware, JSONAware specific behaviours will be omitted at this top level.
+	 * 
+	 * @see com.alibaba.nacos.client.logger.json.JSONValue#toJSONString(Object)
+	 * 
+	 * @param map
+	 * @return JSON text, or "null" if map is null.
+	 */
+	public static String toJSONString(Map map){
+		final StringWriter writer = new StringWriter();
+		
+		try {
+			writeJSONString(map, writer);
+			return writer.toString();
+		} catch (IOException e) {
+			// This should never happen with a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+	
+	public String toJSONString(){
+		return toJSONString(this);
+	}
+	
+	public String toString(){
+		return toJSONString();
+	}
+
+	public static String toString(String key,Object value){
+        StringBuffer sb = new StringBuffer();
+        sb.append('\"');
+        if(key == null) {
+            sb.append("null");
+        }
+        else {
+            JSONValue.escape(key, sb);
+        }
+		sb.append('\"').append(':');
+		
+		sb.append(JSONValue.toJSONString(value));
+		
+		return sb.toString();
+	}
+	
+	/**
+	 * Escape quotes, \, /, \r, \n, \b, \f, \t and other control characters (U+0000 through U+001F).
+	 * It's the same as JSONValue.escape() only for compatibility here.
+	 * 
+	 * @see com.alibaba.nacos.client.logger.json.JSONValue#escape(String)
+	 * 
+	 * @param s
+	 * @return
+	 */
+	public static String escape(String s){
+		return JSONValue.escape(s);
+	}
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/JSONStreamAware.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.json;
+
+import java.io.IOException;
+import java.io.Writer;
+
+/**
+ * Beans that support customized output of JSON text to a writer shall implement
+ * this interface.
+ * 
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public interface JSONStreamAware {
+	/**
+	 * write JSON string to out.
+	 * 
+	 * @param out
+	 *            out writer
+	 * @throws IOException
+	 *             Exception
+	 */
+	void writeJSONString(Writer out) throws IOException;
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/JSONValue.java

@@ -0,0 +1,343 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * $Id: JSONValue.java,v 1.1 2006/04/15 14:37:04 platform Exp $
+ * Created on 2006-4-15
+ */
+package com.alibaba.nacos.client.logger.json;
+
+import java.io.IOException;
+import java.io.Reader;
+import java.io.StringReader;
+import java.io.StringWriter;
+import java.io.Writer;
+import java.util.Collection;
+import java.util.Map;
+
+import com.alibaba.nacos.client.logger.json.parser.JSONParser;
+import com.alibaba.nacos.client.logger.json.parser.ParseException;
+
+
+
+/**
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public class JSONValue {
+	/**
+	 * Parse JSON text into java object from the input source. 
+	 * Please use parseWithException() if you don't want to ignore the exception.
+	 * 
+	 * @see com.alibaba.nacos.client.logger.jsonparser.JSONParser#parse(Reader)
+	 * @see #parseWithException(Reader)
+	 * 
+	 * @param in
+	 * @return Instance of the following:
+	 *	com.alibaba.nacos.client.logger.jsonJSONObject,
+	 * 	com.alibaba.nacos.client.logger.jsonJSONArray,
+	 * 	java.lang.String,
+	 * 	java.lang.Number,
+	 * 	java.lang.Boolean,
+	 * 	null
+	 * 
+	 * @deprecated this method may throw an {@code Error} instead of returning
+	 * {@code null}; please use {@link JSONValue#parseWithException(Reader)}
+	 * instead
+	 */
+	public static Object parse(Reader in){
+		try{
+			JSONParser parser=new JSONParser();
+			return parser.parse(in);
+		}
+		catch(Exception e){
+			return null;
+		}
+	}
+	
+	/**
+	 * Parse JSON text into java object from the given string. 
+	 * Please use parseWithException() if you don't want to ignore the exception.
+	 * 
+	 * @see com.alibaba.nacos.client.logger.jsonparser.JSONParser#parse(Reader)
+	 * @see #parseWithException(Reader)
+	 * 
+	 * @param s
+	 * @return Instance of the following:
+	 *	com.alibaba.nacos.client.logger.jsonJSONObject,
+	 * 	com.alibaba.nacos.client.logger.jsonJSONArray,
+	 * 	java.lang.String,
+	 * 	java.lang.Number,
+	 * 	java.lang.Boolean,
+	 * 	null
+	 * 
+	 * @deprecated this method may throw an {@code Error} instead of returning
+	 * {@code null}; please use {@link JSONValue#parseWithException(String)}
+	 * instead
+	 */
+	public static Object parse(String s){
+		StringReader in=new StringReader(s);
+		return parse(in);
+	}
+	
+	/**
+	 * Parse JSON text into java object from the input source.
+	 * 
+	 * @see com.alibaba.nacos.client.logger.jsonparser.JSONParser
+	 * 
+	 * @param in
+	 * @return Instance of the following:
+	 * 	com.alibaba.nacos.client.logger.jsonJSONObject,
+	 * 	com.alibaba.nacos.client.logger.jsonJSONArray,
+	 * 	java.lang.String,
+	 * 	java.lang.Number,
+	 * 	java.lang.Boolean,
+	 * 	null
+	 * 
+	 * @throws IOException
+	 * @throws ParseException
+	 */
+	public static Object parseWithException(Reader in) throws IOException, ParseException {
+		JSONParser parser=new JSONParser();
+		return parser.parse(in);
+	}
+	
+	public static Object parseWithException(String s) throws ParseException{
+		JSONParser parser=new JSONParser();
+		return parser.parse(s);
+	}
+	
+    /**
+     * Encode an object into JSON text and write it to out.
+     * <p>
+     * If this object is a Map or a List, and it's also a JSONStreamAware or a JSONAware, JSONStreamAware or JSONAware will be considered firstly.
+     * <p>
+     * DO NOT call this method from writeJSONString(Writer) of a class that implements both JSONStreamAware and (Map or List) with 
+     * "this" as the first parameter, use JSONObject.writeJSONString(Map, Writer) or JSONArray.writeJSONString(List, Writer) instead. 
+     * 
+     * @see com.alibaba.nacos.client.logger.jsonJSONObject#writeJSONString(Map, Writer)
+     * @see com.alibaba.nacos.client.logger.jsonJSONArray#writeJSONString(List, Writer)
+     * 
+     * @param value
+     * @param writer
+     */
+	public static void writeJSONString(Object value, Writer out) throws IOException {
+		if(value == null){
+			out.write("null");
+			return;
+		}
+		
+		if(value instanceof String){
+            out.write('\"');
+			out.write(escape((String)value));
+            out.write('\"');
+			return;
+		}
+		
+		if(value instanceof Double){
+			if(((Double)value).isInfinite() || ((Double)value).isNaN()) {
+				out.write("null");
+			}
+			else {
+				out.write(value.toString());
+			}
+			return;
+		}
+		
+		if(value instanceof Float){
+			if(((Float)value).isInfinite() || ((Float)value).isNaN()) {
+				out.write("null");
+			}
+			else {
+				out.write(value.toString());
+			}
+			return;
+		}		
+		
+		if(value instanceof Number){
+			out.write(value.toString());
+			return;
+		}
+		
+		if(value instanceof Boolean){
+			out.write(value.toString());
+			return;
+		}
+		
+		if((value instanceof JSONStreamAware)){
+			((JSONStreamAware)value).writeJSONString(out);
+			return;
+		}
+		
+		if((value instanceof JSONAware)){
+			out.write(((JSONAware)value).toJSONString());
+			return;
+		}
+		
+		if(value instanceof Map){
+			JSONObject.writeJSONString((Map)value, out);
+			return;
+		}
+		
+		if(value instanceof Collection){
+			JSONArray.writeJSONString((Collection)value, out);
+            return;
+		}
+		
+		if(value instanceof byte[]){
+			JSONArray.writeJSONString((byte[])value, out);
+			return;
+		}
+		
+		if(value instanceof short[]){
+			JSONArray.writeJSONString((short[])value, out);
+			return;
+		}
+		
+		if(value instanceof int[]){
+			JSONArray.writeJSONString((int[])value, out);
+			return;
+		}
+		
+		if(value instanceof long[]){
+			JSONArray.writeJSONString((long[])value, out);
+			return;
+		}
+		
+		if(value instanceof float[]){
+			JSONArray.writeJSONString((float[])value, out);
+			return;
+		}
+		
+		if(value instanceof double[]){
+			JSONArray.writeJSONString((double[])value, out);
+			return;
+		}
+		
+		if(value instanceof boolean[]){
+			JSONArray.writeJSONString((boolean[])value, out);
+			return;
+		}
+		
+		if(value instanceof char[]){
+			JSONArray.writeJSONString((char[])value, out);
+			return;
+		}
+		
+		if(value instanceof Object[]){
+			JSONArray.writeJSONString((Object[])value, out);
+			return;
+		}
+		
+		out.write(value.toString());
+	}
+
+	/**
+	 * Convert an object to JSON text.
+	 * <p>
+	 * If this object is a Map or a List, and it's also a JSONAware, JSONAware will be considered firstly.
+	 * <p>
+	 * DO NOT call this method from toJSONString() of a class that implements both JSONAware and Map or List with 
+	 * "this" as the parameter, use JSONObject.toJSONString(Map) or JSONArray.toJSONString(List) instead. 
+	 * 
+	 * @see com.alibaba.nacos.client.logger.json.JSONObject#toJSONString(Map)
+	 *
+	 * @param value
+	 * @return JSON text, or "null" if value is null or it's an NaN or an INF number.
+	 */
+	public static String toJSONString(Object value){
+		final StringWriter writer = new StringWriter();
+		
+		try{
+			writeJSONString(value, writer);
+			return writer.toString();
+		} catch(IOException e){
+			// This should never happen for a StringWriter
+			throw new RuntimeException(e);
+		}
+	}
+
+	/**
+	 * Escape quotes, \, /, \r, \n, \b, \f, \t and other control characters (U+0000 through U+001F).
+	 * @param s
+	 * @return
+	 */
+	public static String escape(String s){
+		if(s==null) {
+			return null;
+		}
+        StringBuffer sb = new StringBuffer();
+        escape(s, sb);
+        return sb.toString();
+    }
+
+    /**
+     * @param s - Must not be null.
+     * @param sb
+     */
+    static void escape(String s, StringBuffer sb) {
+    	final int len = s.length();
+		for(int i=0;i<len;i++){
+			char ch=s.charAt(i);
+			switch(ch){
+			case '"':
+				sb.append("\\\"");
+				break;
+			case '\\':
+				sb.append("\\\\");
+				break;
+			case '\b':
+				sb.append("\\b");
+				break;
+			case '\f':
+				sb.append("\\f");
+				break;
+			case '\n':
+				sb.append("\\n");
+				break;
+			case '\r':
+				sb.append("\\r");
+				break;
+			case '\t':
+				sb.append("\\t");
+				break;
+			case '/':
+				sb.append("\\/");
+				break;
+			default:
+                //Reference: http://www.unicode.org/versions/Unicode5.1.0/
+				if(isUnicodeChar(ch)){
+					String ss=Integer.toHexString(ch);
+					sb.append("\\u");
+					for(int k=0;k<FOUR-ss.length();k++){
+						sb.append('0');
+					}
+					sb.append(ss.toUpperCase());
+				}
+				else{
+					sb.append(ch);
+				}
+			}
+		}//for
+	}
+    
+	private static boolean isUnicodeChar(char ch) {
+		return (ch >= '\u0000' && ch <= '\u001F') || (ch >= '\u007F' && ch <= '\u009F')
+				|| (ch >= '\u2000' && ch <= '\u20FF');
+	}
+	
+	private static int FOUR = 4;
+
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/parser/ContainerFactory.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.json.parser;
+
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Container factory for creating containers for JSON object and JSON array.
+ * 
+ * @see com.alibaba.nacos.client.logger.json.parser.JSONParser#parse(java.io.Reader, ContainerFactory)
+ * 
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ */
+public interface ContainerFactory {
+	/**
+	 * create json container
+	 * @return A Map instance to store JSON object, or null if you want to use com.alibaba.nacos.client.logger.jsonJSONObject.
+	 */
+	Map createObjectContainer();
+	
+	/**
+	 * create array json container
+	 * @return A List instance to store JSON array, or null if you want to use com.alibaba.nacos.client.logger.jsonJSONArray.
+	 */
+	List creatArrayContainer();
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/parser/ContentHandler.java

@@ -0,0 +1,129 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.json.parser;
+
+import java.io.IOException;
+
+/**
+ * A simplified and stoppable SAX-like content handler for stream processing of JSON text. 
+ * 
+ * @see org.xml.sax.ContentHandler
+ * @see com.alibaba.nacos.client.logger.json.parser.JSONParser#parse(java.io.Reader, ContentHandler, boolean)
+ * 
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ */
+public interface ContentHandler {
+	/**
+	 * Receive notification of the beginning of JSON processing.
+	 * The parser will invoke this method only once.
+     * 
+	 * @throws ParseException 
+	 * 			- JSONParser will stop and throw the same exception to the caller when receiving this exception.
+     * @throws IOException
+	 */
+	void startJSON() throws ParseException, IOException;
+	
+	/**
+	 * Receive notification of the end of JSON processing.
+	 * 
+	 * @throws ParseException
+	 * @throws IOException
+	 */
+	void endJSON() throws ParseException, IOException;
+	
+	/**
+	 * Receive notification of the beginning of a JSON object.
+	 * 
+	 * @return false if the handler wants to stop parsing after return.
+	 * @throws ParseException
+     *          - JSONParser will stop and throw the same exception to the caller when receiving this exception.
+     * @throws IOException
+     * @see #endJSON
+	 */
+	boolean startObject() throws ParseException, IOException;
+	
+	/**
+	 * Receive notification of the end of a JSON object.
+	 * 
+	 * @return false if the handler wants to stop parsing after return.
+	 * @throws ParseException
+	 * @throws IOException
+     * @see #startObject
+	 */
+	boolean endObject() throws ParseException, IOException;
+	
+	/**
+	 * Receive notification of the beginning of a JSON object entry.
+	 * 
+	 * @param key - Key of a JSON object entry. 
+	 * 
+	 * @return false if the handler wants to stop parsing after return.
+	 * @throws ParseException
+	 * @throws IOException
+     * @see #endObjectEntry
+	 */
+	boolean startObjectEntry(String key) throws ParseException, IOException;
+	
+	/**
+	 * Receive notification of the end of the value of previous object entry.
+	 * 
+	 * @return false if the handler wants to stop parsing after return.
+	 * @throws ParseException
+	 * @throws IOException
+     * @see #startObjectEntry
+	 */
+	boolean endObjectEntry() throws ParseException, IOException;
+	
+	/**
+	 * Receive notification of the beginning of a JSON array.
+	 * 
+	 * @return false if the handler wants to stop parsing after return.
+	 * @throws ParseException
+	 * @throws IOException
+     * @see #endArray
+	 */
+	boolean startArray() throws ParseException, IOException;
+	
+	/**
+	 * Receive notification of the end of a JSON array.
+	 * 
+	 * @return false if the handler wants to stop parsing after return.
+	 * @throws ParseException
+	 * @throws IOException
+     * @see #startArray
+	 */
+	boolean endArray() throws ParseException, IOException;
+	
+	/**
+	 * Receive notification of the JSON primitive values:
+	 * 	java.lang.String,
+	 * 	java.lang.Number,
+	 * 	java.lang.Boolean
+	 * 	null
+	 * 
+	 * @param value - Instance of the following:
+	 * 			java.lang.String,
+	 * 			java.lang.Number,
+	 * 			java.lang.Boolean
+	 * 			null
+	 * 
+	 * @return false if the handler wants to stop parsing after return.
+	 * @throws ParseException
+	 * @throws IOException
+	 */
+	boolean primitive(Object value) throws ParseException, IOException;
+		
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/parser/JSONParser.java

@@ -0,0 +1,574 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * $Id: JSONParser.java,v 1.1 2006/04/15 14:10:48 platform Exp $
+ * Created on 2006-4-15
+ */
+package com.alibaba.nacos.client.logger.json.parser;
+
+import java.io.IOException;
+import java.io.Reader;
+import java.io.StringReader;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+import com.alibaba.nacos.client.logger.json.JSONArray;
+import com.alibaba.nacos.client.logger.json.JSONObject;
+
+
+/**
+ * Parser for JSON text. Please note that JSONParser is NOT thread-safe.
+ * 
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ */
+@SuppressWarnings("PMD.ClassNamingShouldBeCamelRule")
+public class JSONParser {
+	public static final int S_INIT=0;
+	public static final int S_IN_FINISHED_VALUE=1;
+	public static final int S_IN_OBJECT=2;
+	public static final int S_IN_ARRAY=3;
+	public static final int S_PASSED_PAIR_KEY=4;
+	public static final int S_IN_PAIR_VALUE=5;
+	public static final int S_END=6;
+	public static final int S_IN_ERROR=-1;
+	
+	private LinkedList handlerStatusStack;
+	private Yylex lexer = new Yylex((Reader)null);
+	private Yytoken token = null;
+	private int status = S_INIT;
+	
+	private int peekStatus(LinkedList statusStack){
+		if(statusStack.size()==0) {
+			return -1;
+		}
+		Integer status=(Integer)statusStack.getFirst();
+		return status.intValue();
+	}
+	
+    /**
+     *  Reset the parser to the initial state without resetting the underlying reader.
+     *
+     */
+    public void reset(){
+        token = null;
+        status = S_INIT;
+        handlerStatusStack = null;
+    }
+    
+    /**
+     * Reset the parser to the initial state with a new character reader.
+     * 
+     * @param in - The new character reader.
+     * @throws IOException
+     * @throws ParseException
+     */
+	public void reset(Reader in){
+		lexer.yyreset(in);
+		reset();
+	}
+	
+	/**
+	 * @return The position of the beginning of the current token.
+	 */
+	public int getPosition(){
+		return lexer.getPosition();
+	}
+	
+	public Object parse(String s) throws ParseException{
+		return parse(s, (ContainerFactory)null);
+	}
+	
+	public Object parse(String s, ContainerFactory containerFactory) throws ParseException{
+		StringReader in=new StringReader(s);
+		try{
+			return parse(in, containerFactory);
+		}
+		catch(IOException ie){
+			/*
+			 * Actually it will never happen.
+			 */
+			throw new ParseException(-1, ParseException.ERROR_UNEXPECTED_EXCEPTION, ie);
+		}
+	}
+	
+	public Object parse(Reader in) throws IOException, ParseException{
+		return parse(in, (ContainerFactory)null);
+	}
+	
+	/**
+	 * Parse JSON text into java object from the input source.
+	 * 	
+	 * @param in
+     * @param containerFactory - Use this factory to createyour own JSON object and JSON array containers.
+	 * @return Instance of the following:
+	 *  com.alibaba.nacos.client.logger.jsonJSONObject,
+	 * 	com.alibaba.nacos.client.logger.jsonJSONArray,
+	 * 	java.lang.String,
+	 * 	java.lang.Number,
+	 * 	java.lang.Boolean,
+	 * 	null
+	 * 
+	 * @throws IOException
+	 * @throws ParseException
+	 */
+	public Object parse(Reader in, ContainerFactory containerFactory) throws IOException, ParseException{
+		reset(in);
+		LinkedList statusStack = new LinkedList();
+		LinkedList valueStack = new LinkedList();
+		
+		try{
+			do{
+				nextToken();
+				switch(status){
+				case S_INIT:
+					switch(token.type){
+					case Yytoken.TYPE_VALUE:
+						status=S_IN_FINISHED_VALUE;
+						statusStack.addFirst(Integer.valueOf(status));
+						valueStack.addFirst(token.value);
+						break;
+					case Yytoken.TYPE_LEFT_BRACE:
+						status=S_IN_OBJECT;
+						statusStack.addFirst(Integer.valueOf(status));
+						valueStack.addFirst(createObjectContainer(containerFactory));
+						break;
+					case Yytoken.TYPE_LEFT_SQUARE:
+						status=S_IN_ARRAY;
+						statusStack.addFirst(Integer.valueOf(status));
+						valueStack.addFirst(createArrayContainer(containerFactory));
+						break;
+					default:
+						status=S_IN_ERROR;
+					}//inner switch
+					break;
+					
+				case S_IN_FINISHED_VALUE:
+					if(token.type==Yytoken.TYPE_EOF) {
+						return valueStack.removeFirst();
+					}
+					else {
+						throw new ParseException(getPosition(), ParseException.ERROR_UNEXPECTED_TOKEN, token);
+					}
+				case S_IN_OBJECT:
+					switch(token.type){
+					case Yytoken.TYPE_COMMA:
+						break;
+					case Yytoken.TYPE_VALUE:
+						if(token.value instanceof String){
+							String key=(String)token.value;
+							valueStack.addFirst(key);
+							status=S_PASSED_PAIR_KEY;
+							statusStack.addFirst(Integer.valueOf(status));
+						}
+						else{
+							status=S_IN_ERROR;
+						}
+						break;
+					case Yytoken.TYPE_RIGHT_BRACE:
+						if(valueStack.size()>1){
+							statusStack.removeFirst();
+							valueStack.removeFirst();
+							status=peekStatus(statusStack);
+						}
+						else{
+							status=S_IN_FINISHED_VALUE;
+						}
+						break;
+					default:
+						status=S_IN_ERROR;
+						break;
+					}//inner switch
+					break;
+					
+				case S_PASSED_PAIR_KEY:
+					switch(token.type){
+					case Yytoken.TYPE_COLON:
+						break;
+					case Yytoken.TYPE_VALUE:
+						statusStack.removeFirst();
+						String key=(String)valueStack.removeFirst();
+						Map parent=(Map)valueStack.getFirst();
+						parent.put(key,token.value);
+						status=peekStatus(statusStack);
+						break;
+					case Yytoken.TYPE_LEFT_SQUARE:
+						statusStack.removeFirst();
+						key=(String)valueStack.removeFirst();
+						parent=(Map)valueStack.getFirst();
+						List newArray=createArrayContainer(containerFactory);
+						parent.put(key,newArray);
+						status=S_IN_ARRAY;
+						statusStack.addFirst(Integer.valueOf(status));
+						valueStack.addFirst(newArray);
+						break;
+					case Yytoken.TYPE_LEFT_BRACE:
+						statusStack.removeFirst();
+						key=(String)valueStack.removeFirst();
+						parent=(Map)valueStack.getFirst();
+						Map newObject=createObjectContainer(containerFactory);
+						parent.put(key,newObject);
+						status=S_IN_OBJECT;
+						statusStack.addFirst(Integer.valueOf(status));
+						valueStack.addFirst(newObject);
+						break;
+					default:
+						status=S_IN_ERROR;
+					}
+					break;
+					
+				case S_IN_ARRAY:
+					switch(token.type){
+					case Yytoken.TYPE_COMMA:
+						break;
+					case Yytoken.TYPE_VALUE:
+						List val=(List)valueStack.getFirst();
+						val.add(token.value);
+						break;
+					case Yytoken.TYPE_RIGHT_SQUARE:
+						if(valueStack.size()>1){
+							statusStack.removeFirst();
+							valueStack.removeFirst();
+							status=peekStatus(statusStack);
+						}
+						else{
+							status=S_IN_FINISHED_VALUE;
+						}
+						break;
+					case Yytoken.TYPE_LEFT_BRACE:
+						val=(List)valueStack.getFirst();
+						Map newObject=createObjectContainer(containerFactory);
+						val.add(newObject);
+						status=S_IN_OBJECT;
+						statusStack.addFirst(Integer.valueOf(status));
+						valueStack.addFirst(newObject);
+						break;
+					case Yytoken.TYPE_LEFT_SQUARE:
+						val=(List)valueStack.getFirst();
+						List newArray=createArrayContainer(containerFactory);
+						val.add(newArray);
+						status=S_IN_ARRAY;
+						statusStack.addFirst(Integer.valueOf(status));
+						valueStack.addFirst(newArray);
+						break;
+					default:
+						status=S_IN_ERROR;
+					}//inner switch
+					break;
+				case S_IN_ERROR:
+					throw new ParseException(getPosition(), ParseException.ERROR_UNEXPECTED_TOKEN, token);
+			    default:
+			    	break;
+				}//switch
+				if(status==S_IN_ERROR){
+					throw new ParseException(getPosition(), ParseException.ERROR_UNEXPECTED_TOKEN, token);
+				}
+			}while(token.type!=Yytoken.TYPE_EOF);
+		}
+		catch(IOException ie){
+			throw ie;
+		}
+		
+		throw new ParseException(getPosition(), ParseException.ERROR_UNEXPECTED_TOKEN, token);
+	}
+	
+	private void nextToken() throws ParseException, IOException{
+		token = lexer.yylex();
+		if(token == null) {
+			token = new Yytoken(Yytoken.TYPE_EOF, null);
+		}
+	}
+	
+	private Map createObjectContainer(ContainerFactory containerFactory){
+		if(containerFactory == null) {
+			return new JSONObject();
+		}
+		Map m = containerFactory.createObjectContainer();
+		
+		if(m == null) {
+			return new JSONObject();
+		}
+		return m;
+	}
+	
+	private List createArrayContainer(ContainerFactory containerFactory){
+		if(containerFactory == null) {
+			return new JSONArray();
+		}
+		List l = containerFactory.creatArrayContainer();
+		
+		if(l == null) {
+			return new JSONArray();
+		}
+		return l;
+	}
+	
+	public void parse(String s, ContentHandler contentHandler) throws ParseException{
+		parse(s, contentHandler, false);
+	}
+	
+	public void parse(String s, ContentHandler contentHandler, boolean isResume) throws ParseException{
+		StringReader in=new StringReader(s);
+		try{
+			parse(in, contentHandler, isResume);
+		}
+		catch(IOException ie){
+			/*
+			 * Actually it will never happen.
+			 */
+			throw new ParseException(-1, ParseException.ERROR_UNEXPECTED_EXCEPTION, ie);
+		}
+	}
+	
+	public void parse(Reader in, ContentHandler contentHandler) throws IOException, ParseException{
+		parse(in, contentHandler, false);
+	}
+	
+	/**
+	 * Stream processing of JSON text.
+	 * 
+	 * @see ContentHandler
+	 * 
+	 * @param in
+	 * @param contentHandler
+	 * @param isResume - Indicates if it continues previous parsing operation.
+     *                   If set to true, resume parsing the old stream, and parameter 'in' will be ignored. 
+	 *                   If this method is called for the first time in this instance, isResume will be ignored.
+	 * 
+	 * @throws IOException
+	 * @throws ParseException
+	 */
+	public void parse(Reader in, ContentHandler contentHandler, boolean isResume) throws IOException, ParseException{
+		if(!isResume){
+			reset(in);
+			handlerStatusStack = new LinkedList();
+		}
+		else{
+			if(handlerStatusStack == null){
+				isResume = false;
+				reset(in);
+				handlerStatusStack = new LinkedList();
+			}
+		}
+		
+		LinkedList statusStack = handlerStatusStack;	
+		
+		try{
+			do{
+				switch(status){
+				case S_INIT:
+					contentHandler.startJSON();
+					nextToken();
+					switch(token.type){
+					case Yytoken.TYPE_VALUE:
+						status=S_IN_FINISHED_VALUE;
+						statusStack.addFirst(Integer.valueOf(status));
+						if(!contentHandler.primitive(token.value)) {
+							return;
+						}
+						break;
+					case Yytoken.TYPE_LEFT_BRACE:
+						status=S_IN_OBJECT;
+						statusStack.addFirst(Integer.valueOf(status));
+						if(!contentHandler.startObject()) {
+							return;
+						}
+						break;
+					case Yytoken.TYPE_LEFT_SQUARE:
+						status=S_IN_ARRAY;
+						statusStack.addFirst(Integer.valueOf(status));
+						if(!contentHandler.startArray()) {
+							return;
+						}
+						break;
+					default:
+						status=S_IN_ERROR;
+					}//inner switch
+					break;
+					
+				case S_IN_FINISHED_VALUE:
+					nextToken();
+					if(token.type==Yytoken.TYPE_EOF){
+						contentHandler.endJSON();
+						status = S_END;
+						return;
+					}
+					else{
+						status = S_IN_ERROR;
+						throw new ParseException(getPosition(), ParseException.ERROR_UNEXPECTED_TOKEN, token);
+					}
+			
+				case S_IN_OBJECT:
+					nextToken();
+					switch(token.type){
+					case Yytoken.TYPE_COMMA:
+						break;
+					case Yytoken.TYPE_VALUE:
+						if(token.value instanceof String){
+							String key=(String)token.value;
+							status=S_PASSED_PAIR_KEY;
+							statusStack.addFirst(Integer.valueOf(status));
+							if(!contentHandler.startObjectEntry(key)) {
+								return;
+							}
+						}
+						else{
+							status=S_IN_ERROR;
+						}
+						break;
+					case Yytoken.TYPE_RIGHT_BRACE:
+						if(statusStack.size()>1){
+							statusStack.removeFirst();
+							status=peekStatus(statusStack);
+						}
+						else{
+							status=S_IN_FINISHED_VALUE;
+						}
+						if(!contentHandler.endObject()) {
+							return;
+						}
+						break;
+					default:
+						status=S_IN_ERROR;
+						break;
+					}//inner switch
+					break;
+					
+				case S_PASSED_PAIR_KEY:
+					nextToken();
+					switch(token.type){
+					case Yytoken.TYPE_COLON:
+						break;
+					case Yytoken.TYPE_VALUE:
+						statusStack.removeFirst();
+						status=peekStatus(statusStack);
+						if(!contentHandler.primitive(token.value)) {
+							return;
+						}
+						if(!contentHandler.endObjectEntry()) {
+							return;
+						}
+						break;
+					case Yytoken.TYPE_LEFT_SQUARE:
+						statusStack.removeFirst();
+						statusStack.addFirst(Integer.valueOf(S_IN_PAIR_VALUE));
+						status=S_IN_ARRAY;
+						statusStack.addFirst(Integer.valueOf(status));
+						if(!contentHandler.startArray()) {
+							return;
+						}
+						break;
+					case Yytoken.TYPE_LEFT_BRACE:
+						statusStack.removeFirst();
+						statusStack.addFirst(Integer.valueOf(S_IN_PAIR_VALUE));
+						status=S_IN_OBJECT;
+						statusStack.addFirst(Integer.valueOf(status));
+						if(!contentHandler.startObject()) {
+							return;
+						}
+						break;
+					default:
+						status=S_IN_ERROR;
+					}
+					break;
+				
+				case S_IN_PAIR_VALUE:
+					/*
+					 * S_IN_PAIR_VALUE is just a marker to indicate the end of an object entry, it doesn't proccess any token,
+					 * therefore delay consuming token until next round.
+					 */
+					statusStack.removeFirst();
+					status = peekStatus(statusStack);
+					if(!contentHandler.endObjectEntry()) {
+						return;
+					}
+					break;
+					
+				case S_IN_ARRAY:
+					nextToken();
+					switch(token.type){
+					case Yytoken.TYPE_COMMA:
+						break;
+					case Yytoken.TYPE_VALUE:
+						if(!contentHandler.primitive(token.value)) {
+							return;
+						}
+						break;
+					case Yytoken.TYPE_RIGHT_SQUARE:
+						if(statusStack.size()>1){
+							statusStack.removeFirst();
+							status=peekStatus(statusStack);
+						}
+						else{
+							status=S_IN_FINISHED_VALUE;
+						}
+						if(!contentHandler.endArray()) {
+							return;
+						}
+						break;
+					case Yytoken.TYPE_LEFT_BRACE:
+						status=S_IN_OBJECT;
+						statusStack.addFirst(Integer.valueOf(status));
+						if(!contentHandler.startObject()) {
+							return;
+						}
+						break;
+					case Yytoken.TYPE_LEFT_SQUARE:
+						status=S_IN_ARRAY;
+						statusStack.addFirst(Integer.valueOf(status));
+						if(!contentHandler.startArray()) {
+							return;
+						}
+						break;
+					default:
+						status=S_IN_ERROR;
+					}//inner switch
+					break;
+					
+				case S_END:
+					return;
+					
+				case S_IN_ERROR:
+					throw new ParseException(getPosition(), ParseException.ERROR_UNEXPECTED_TOKEN, token);
+				default:
+					break;
+				}//switch
+				if(status==S_IN_ERROR){
+					throw new ParseException(getPosition(), ParseException.ERROR_UNEXPECTED_TOKEN, token);
+				}
+			}while(token.type!=Yytoken.TYPE_EOF);
+		}
+		catch(IOException ie){
+			status = S_IN_ERROR;
+			throw ie;
+		}
+		catch(ParseException pe){
+			status = S_IN_ERROR;
+			throw pe;
+		}
+		catch(RuntimeException re){
+			status = S_IN_ERROR;
+			throw re;
+		}
+		catch(Error e){
+			status = S_IN_ERROR;
+			throw e;
+		}
+		
+		status = S_IN_ERROR;
+		throw new ParseException(getPosition(), ParseException.ERROR_UNEXPECTED_TOKEN, token);
+	}
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/parser/ParseException.java

@@ -0,0 +1,105 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.json.parser;
+
+/**
+ * ParseException explains why and where the error occurs in source JSON text.
+ * 
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ *
+ */
+public class ParseException extends Exception {
+	private static final long serialVersionUID = -7880698968187728547L;
+	
+	public static final int ERROR_UNEXPECTED_CHAR = 0;
+	public static final int ERROR_UNEXPECTED_TOKEN = 1;
+	public static final int ERROR_UNEXPECTED_EXCEPTION = 2;
+
+	private int errorType;
+	private Object unexpectedObject;
+	private int position;
+	
+	public ParseException(int errorType){
+		this(-1, errorType, null);
+	}
+	
+	public ParseException(int errorType, Object unexpectedObject){
+		this(-1, errorType, unexpectedObject);
+	}
+	
+	public ParseException(int position, int errorType, Object unexpectedObject){
+		this.position = position;
+		this.errorType = errorType;
+		this.unexpectedObject = unexpectedObject;
+	}
+	
+	public int getErrorType() {
+		return errorType;
+	}
+	
+	public void setErrorType(int errorType) {
+		this.errorType = errorType;
+	}
+	
+	/**
+	 * @see com.alibaba.nacos.client.logger.json.parser.JSONParser#getPosition()
+	 * 
+	 * @return The character position (starting with 0) of the input where the error occurs.
+	 */
+	public int getPosition() {
+		return position;
+	}
+	
+	public void setPosition(int position) {
+		this.position = position;
+	}
+	
+	/**
+	 * @see com.alibaba.nacos.client.logger.json.parser.Yytoken
+	 * 
+	 * @return One of the following base on the value of errorType:
+	 * 		   	ERROR_UNEXPECTED_CHAR		java.lang.Character
+	 * 			ERROR_UNEXPECTED_TOKEN		com.alibaba.nacos.client.logger.jsonparser.Yytoken
+	 * 			ERROR_UNEXPECTED_EXCEPTION	java.lang.Exception
+	 */
+	public Object getUnexpectedObject() {
+		return unexpectedObject;
+	}
+	
+	public void setUnexpectedObject(Object unexpectedObject) {
+		this.unexpectedObject = unexpectedObject;
+	}
+	
+	public String getMessage() {
+		StringBuffer sb = new StringBuffer();
+		
+		switch(errorType){
+		case ERROR_UNEXPECTED_CHAR:
+			sb.append("Unexpected character (").append(unexpectedObject).append(") at position ").append(position).append(".");
+			break;
+		case ERROR_UNEXPECTED_TOKEN:
+			sb.append("Unexpected token ").append(unexpectedObject).append(" at position ").append(position).append(".");
+			break;
+		case ERROR_UNEXPECTED_EXCEPTION:
+			sb.append("Unexpected exception at position ").append(position).append(": ").append(unexpectedObject);
+			break;
+		default:
+			sb.append("Unkown error at position ").append(position).append(".");
+			break;
+		}
+		return sb.toString();
+	}
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/parser/Yylex.java

@@ -0,0 +1,665 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/* The following code was generated by JFlex 1.4.2 */
+
+package com.alibaba.nacos.client.logger.json.parser;
+
+import java.io.UnsupportedEncodingException;
+
+import com.alibaba.nacos.client.config.common.Constants;
+
+/**
+ * Yylex
+ * @author Nacos
+ *
+ */
+class Yylex {
+
+    /** This character denotes the end of file */
+    public static final int YYEOF = -1;
+
+    /** initial size of the lookahead buffer */
+    private static final int ZZ_BUFFERSIZE = 16384;
+
+    /** lexical states */
+    public static final int YYINITIAL = 0;
+    public static final int STRING_BEGIN = 2;
+
+    /**
+     * ZZ_LEXSTATE[l] is the state in the DFA for the lexical state l
+     * ZZ_LEXSTATE[l+1] is the state in the DFA for the lexical state l
+     * at the beginning of a line
+     * l is of the form l = 2*k, k a non negative integer
+     */
+    private static final int ZZ_LEXSTATE[] = { 0, 0, 1, 1 };
+
+    /**
+     * Translates characters to character classes
+     */
+    private static final String ZZ_CMAP_PACKED =
+            "\11\0\1\7\1\7\2\0\1\7\22\0\1\7\1\0\1\11\10\0" + "\1\6\1\31\1\2\1\4\1\12\12\3\1\32\6\0\4\1\1\5"
+            + "\1\1\24\0\1\27\1\10\1\30\3\0\1\22\1\13\2\1\1\21" + "\1\14\5\0\1\23\1\0\1\15\3\0\1\16\1\24\1\17\1\20"
+            + "\5\0\1\25\1\0\1\26\uff82\0";
+
+    /**
+     * Translates characters to character classes
+     */
+    private static final char[] ZZ_CMAP = zzUnpackCMap(ZZ_CMAP_PACKED);
+
+    /**
+     * Translates DFA states to action switch labels.
+     */
+    private static final int[] ZZ_ACTION = zzUnpackAction();
+
+    private static final String ZZ_ACTION_PACKED_0 =
+            "\2\0\2\1\1\2\1\3\1\4\3\1\1\5\1\6" + "\1\7\1\10\1\11\1\12\1\13\1\14\1\15\5\0"
+            + "\1\14\1\16\1\17\1\20\1\21\1\22\1\23\1\24" + "\1\0\1\25\1\0\1\25\4\0\1\26\1\27\2\0" + "\1\30";
+
+    private static int[] zzUnpackAction() {
+        int[] result = new int[45];
+        int offset = 0;
+        zzUnpackAction(ZZ_ACTION_PACKED_0, offset, result);
+        return result;
+    }
+
+    private static int zzUnpackAction(String packed, int offset, int[] result) {
+        int i = 0;
+        int j = offset;
+        int l = packed.length();
+        while (i < l) {
+            int count = packed.charAt(i++);
+            int value = packed.charAt(i++);
+            do result[j++] = value; while (--count > 0);
+        }
+        return j;
+    }
+
+    /**
+     * Translates a state to a row index in the transition table
+     */
+    private static final int[] ZZ_ROWMAP = zzUnpackRowMap();
+
+    private static final String ZZ_ROWMAP_PACKED_0 =
+            "\0\0\0\33\0\66\0\121\0\154\0\207\0\66\0\242" + "\0\275\0\330\0\66\0\66\0\66\0\66\0\66\0\66"
+            + "\0\363\0\u010e\0\66\0\u0129\0\u0144\0\u015f\0\u017a\0\u0195" + "\0\66\0\66\0\66\0\66\0\66\0\66\0\66\0\66"
+            + "\0\u01b0\0\u01cb\0\u01e6\0\u01e6\0\u0201\0\u021c\0\u0237\0\u0252" + "\0\66\0\66\0\u026d\0\u0288\0\66";
+
+    private static int[] zzUnpackRowMap() {
+        int[] result = new int[45];
+        int offset = 0;
+        zzUnpackRowMap(ZZ_ROWMAP_PACKED_0, offset, result);
+        return result;
+    }
+
+    private static int zzUnpackRowMap(String packed, int offset, int[] result) {
+        int i = 0;
+        int j = offset;
+        int l = packed.length();
+        while (i < l) {
+            int high = packed.charAt(i++) << 16;
+            result[j++] = high | packed.charAt(i++);
+        }
+        return j;
+    }
+
+    /**
+     * The transition table of the DFA
+     */
+    private static final int ZZ_TRANS[] = { 2, 2, 3, 4, 2, 2, 2, 5, 2, 6, 2, 2, 7, 8, 2, 9, 2, 2, 2, 2, 2, 10, 11, 12,
+                                            13, 14, 15, 16, 16, 16, 16, 16, 16, 16, 16, 17, 18, 16, 16, 16, 16, 16, 16,
+                                            16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 4, 19, 20, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, 20, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, 21, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 22, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 23, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 16, 16, 16, 16, 16, 16, 16, 16, -1,
+                                            -1, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, 24, 25, 26, 27, 28, 29, 30, 31, 32, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 33, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 34, 35,
+                                            -1, -1, 34, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, 36, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 37, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 38, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 39, -1, 39, -1, 39, -1, -1, -1, -1,
+                                            -1, 39, 39, -1, -1, -1, -1, 39, 39, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, 33, -1, 20, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 20, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, 35, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 38, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, 40, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, 41, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+                                            -1, 42, -1, 42, -1, 42, -1, -1, -1, -1, -1, 42, 42, -1, -1, -1, -1, 42, 42,
+                                            -1, -1, -1, -1, -1, -1, -1, -1, -1, 43, -1, 43, -1, 43, -1, -1, -1, -1, -1,
+                                            43, 43, -1, -1, -1, -1, 43, 43, -1, -1, -1, -1, -1, -1, -1, -1, -1, 44, -1,
+                                            44, -1, 44, -1, -1, -1, -1, -1, 44, 44, -1, -1, -1, -1, 44, 44, -1, -1, -1,
+                                            -1, -1, -1, -1, -1, };
+
+    /**
+     * error codes
+     */
+    private static final int ZZ_UNKNOWN_ERROR = 0;
+    private static final int ZZ_NO_MATCH = 1;
+    private static final int ZZ_PUSHBACK_2BIG = 2;
+    private static final int NIGTY = 90;
+    /**
+     * error messages for the codes above 
+     */
+	private static final String[] ZZ_ERROR_MSG = { "Unkown internal scanner error", "Error: could not match input",
+                                                   "Error: pushback value was too large" };
+
+    /**
+     * ZZ_ATTRIBUTE[aState] contains the attributes of state <code>aState</code>
+     */
+    private static final int[] ZZ_ATTRIBUTE = zzUnpackAttribute();
+
+    private static final String ZZ_ATTRIBUTE_PACKED_0 =
+            "\2\0\1\11\3\1\1\11\3\1\6\11\2\1\1\11" + "\5\0\10\11\1\0\1\1\1\0\1\1\4\0\2\11" + "\2\0\1\11";
+
+    private static int[] zzUnpackAttribute() {
+        int[] result = new int[45];
+        int offset = 0;
+        zzUnpackAttribute(ZZ_ATTRIBUTE_PACKED_0, offset, result);
+        return result;
+    }
+
+    private static int zzUnpackAttribute(String packed, int offset, int[] result) {
+        int i = 0;
+        int j = offset; 
+        int l = packed.length();
+        while (i < l) {
+            int count = packed.charAt(i++);
+            int value = packed.charAt(i++);
+            do result[j++] = value; while (--count > 0);
+        }
+        return j;
+    }
+
+    /** the input device */
+    private java.io.Reader zzReader;
+
+    /** the current state of the DFA */
+    private int zzState;
+
+    /** the current lexical state */
+    private int zzLexicalState = YYINITIAL;
+
+    /**
+     * this buffer contains the current text to be matched and is
+     * the source of the yytext() string
+     */
+    private char zzBuffer[] = new char[ZZ_BUFFERSIZE];
+
+    /** the textposition at the last accepting state */
+    private int zzMarkedPos;
+
+    /** the current text position in the buffer */
+    private int zzCurrentPos;
+
+    /** startRead marks the beginning of the yytext() string in the buffer */
+    private int zzStartRead;
+
+    /**
+     * endRead marks the last character in the buffer, that has been read
+     * from input
+     */
+    private int zzEndRead;
+
+    /** the number of characters up to the start of the matched text */
+    private int yychar;
+
+    /** zzAtEOF == true <=> the scanner is at the EOF */
+    private boolean zzAtEOF;
+
+    /**
+     * user code
+     */
+    private StringBuffer sb = new StringBuffer();
+
+    int getPosition() {
+        return yychar;
+    }
+
+    /**
+     * Creates a new scanner
+     * There is also a java.io.InputStream version of this constructor.
+     *
+     * @param in the java.io.Reader to read input from.
+     */
+    Yylex(java.io.Reader in) {
+        this.zzReader = in;
+    }
+
+    /**
+     * Creates a new scanner.
+     * There is also java.io.Reader version of this constructor.
+     *
+     * @param in the java.io.Inputstream to read input from.
+     * @throws UnsupportedEncodingException 
+     */
+    Yylex(java.io.InputStream in) throws UnsupportedEncodingException {
+        this(new java.io.InputStreamReader(in, Constants.ENCODE));
+    }
+
+    /**
+     * Unpacks the compressed character translation table.
+     *
+     * @param packed the packed character translation table
+     * @return the unpacked character translation table
+     */
+    private static char[] zzUnpackCMap(String packed) {
+        char[] map = new char[0x10000];
+        int i = 0;  
+        int j = 0;  
+        while (i < NIGTY) {
+            int count = packed.charAt(i++);
+            char value = packed.charAt(i++);
+            do map[j++] = value; while (--count > 0);
+        }
+        return map;
+    }
+
+    /**
+     * Refills the input buffer.
+     *
+     * @return <code>false</code>, iff there was new input.
+     * @throws java.io.IOException if any I/O-Error occurs
+     */
+    private boolean zzRefill() throws java.io.IOException {
+
+    /* first: make room (if you can) */
+        if (zzStartRead > 0) {
+            System.arraycopy(zzBuffer, zzStartRead, zzBuffer, 0, zzEndRead - zzStartRead);
+
+      /* translate stored positions */
+            zzEndRead -= zzStartRead;
+            zzCurrentPos -= zzStartRead;
+            zzMarkedPos -= zzStartRead;
+            zzStartRead = 0;
+        }
+
+    /* is the buffer big enough? */
+        if (zzCurrentPos >= zzBuffer.length) {
+      /* if not: blow it up */
+            char newBuffer[] = new char[zzCurrentPos * 2];
+            System.arraycopy(zzBuffer, 0, newBuffer, 0, zzBuffer.length);
+            zzBuffer = newBuffer;
+        }
+
+    /* finally: fill the buffer with new input */
+        int numRead = zzReader.read(zzBuffer, zzEndRead, zzBuffer.length - zzEndRead);
+
+        if (numRead > 0) {
+            zzEndRead += numRead;
+            return false;
+        }
+        // unlikely but not impossible: read 0 characters, but not at end of stream    
+        if (numRead == 0) {
+            int c = zzReader.read();
+            if (c == -1) {
+                return true;
+            } else {
+                zzBuffer[zzEndRead++] = (char) c;
+                return false;
+            }
+        }
+
+        // numRead < 0
+        return true;
+    }
+
+    /**
+     * Closes the input stream.
+     */
+    public final void yyclose() throws java.io.IOException {
+        zzAtEOF = true;
+        zzEndRead = zzStartRead; 
+
+        if (zzReader != null) {
+        	zzReader.close();
+        }
+    }
+
+    /**
+     * Resets the scanner to read from a new input stream.
+     * Does not close the old reader.
+     * All internal variables are reset, the old input stream
+     * <b>cannot</b> be reused (internal buffer is discarded and lost).
+     * Lexical state is set to <tt>ZZ_INITIAL</tt>.
+     *
+     * @param reader the new input stream
+     */
+    public final void yyreset(java.io.Reader reader) {
+        zzReader = reader;
+        zzAtEOF = false;
+        zzEndRead = zzStartRead = 0;
+        zzCurrentPos = zzMarkedPos = 0;
+        zzLexicalState = YYINITIAL;
+    }
+
+    /**
+     * Returns the current lexical state.
+     */
+    public final int yystate() {
+        return zzLexicalState;
+    }
+
+    /**
+     * Enters a new lexical state
+     *
+     * @param newState the new lexical state
+     */
+    public final void yybegin(int newState) {
+        zzLexicalState = newState;
+    }
+
+    /**
+     * Returns the text matched by the current regular expression.
+     */
+    public final String yytext() {
+        return new String(zzBuffer, zzStartRead, zzMarkedPos - zzStartRead);
+    }
+
+    /**
+     * Returns the character at position <tt>pos</tt> from the
+     * matched text.
+     * It is equivalent to yytext().charAt(pos), but faster
+     *
+     * @param pos the position of the character to fetch.
+     *            A value from 0 to yylength()-1.
+     * @return the character at position pos
+     */
+    public final char yycharat(int pos) {
+        return zzBuffer[zzStartRead + pos];
+    }
+
+    /**
+     * Returns the length of the matched text region.
+     */
+    public final int yylength() {
+        return zzMarkedPos - zzStartRead;
+    }
+
+    /**
+     * Reports an error that occured while scanning.
+     * In a wellformed scanner (no or only correct usage of
+     * yypushback(int) and a match-all fallback rule) this method
+     * will only be called with things that "Can't Possibly Happen".
+     * If this method is called, something is seriously wrong
+     * (e.g. a JFlex bug producing a faulty scanner etc.).
+     * Usual syntax/scanner level error handling should be done
+     * in error fallback rules.
+     *
+     * @param errorCode the code of the errormessage to display
+     */
+    private void zzScanError(int errorCode) {
+        String message;
+        try {
+            message = ZZ_ERROR_MSG[errorCode];
+        } catch (ArrayIndexOutOfBoundsException e) {
+            message = ZZ_ERROR_MSG[ZZ_UNKNOWN_ERROR];
+        }
+
+        throw new Error(message);
+    }
+
+    /**
+     * Pushes the specified amount of characters back into the input stream.
+     * They will be read again by then next call of the scanning method
+     *
+     * @param number the number of characters to be read again.
+     *               This number must not be greater than yylength()!
+     */
+    public void yypushback(int number) {
+        if (number > yylength()) {
+        	zzScanError(ZZ_PUSHBACK_2BIG);
+        }
+
+        zzMarkedPos -= number;
+    }
+
+    /**
+     * Resumes scanning until the next regular expression is matched,
+     * the end of input is encountered or an I/O-Error occurs.
+     *
+     * @return the next token
+     * @throws java.io.IOException if any I/O-Error occurs
+     */
+    @SuppressWarnings("PMD.SwitchStatementRule")
+    public Yytoken yylex() throws java.io.IOException, ParseException {
+        int zzInput;
+        int zzAction;
+
+        // cached fields:
+        int zzCurrentPosL;
+        int zzMarkedPosL;
+        int zzEndReadL = zzEndRead;
+        char[] zzBufferL = zzBuffer;
+        char[] zzCMapL = ZZ_CMAP;
+
+        int[] zzTransL = ZZ_TRANS;
+        int[] zzRowMapL = ZZ_ROWMAP;
+        int[] zzAttrL = ZZ_ATTRIBUTE;
+
+        while (true) {
+            zzMarkedPosL = zzMarkedPos;
+
+            yychar += zzMarkedPosL - zzStartRead;
+
+            zzAction = -1;
+
+            zzCurrentPosL = zzCurrentPos = zzStartRead = zzMarkedPosL;
+
+            zzState = ZZ_LEXSTATE[zzLexicalState];
+
+            zzForAction:
+            {
+                while (true) {
+
+					if (zzCurrentPosL < zzEndReadL) {
+						zzInput = zzBufferL[zzCurrentPosL++];
+					}
+                    else if (zzAtEOF) {
+                        zzInput = YYEOF;
+                        break zzForAction;
+                    } else {
+                        // store back cached positions
+                        zzCurrentPos = zzCurrentPosL;
+                        zzMarkedPos = zzMarkedPosL;
+                        boolean eof = zzRefill();
+                        // get translated positions and possibly new buffer
+                        zzCurrentPosL = zzCurrentPos;
+                        zzMarkedPosL = zzMarkedPos;
+                        zzBufferL = zzBuffer;
+                        zzEndReadL = zzEndRead;
+                        if (eof) {
+                            zzInput = YYEOF;
+                            break zzForAction;
+                        } else {
+                            zzInput = zzBufferL[zzCurrentPosL++];
+                        }
+                    }
+                    int zzNext = zzTransL[zzRowMapL[zzState] + zzCMapL[zzInput]];
+					if (zzNext == -1) {
+						break zzForAction;
+					}
+                    zzState = zzNext;
+
+                    int zzAttributes = zzAttrL[zzState];
+                    if ((zzAttributes & 1) == 1) {
+                        zzAction = zzState;
+                        zzMarkedPosL = zzCurrentPosL;
+						if ((zzAttributes & 8) == 8) {
+							break zzForAction;
+						}
+                    }
+
+                }
+            }
+
+            // store back cached position
+            zzMarkedPos = zzMarkedPosL;
+            
+            switch (zzAction < 0 ? zzAction : ZZ_ACTION[zzAction]) {
+                case 11: {
+                    sb.append(yytext());
+                }
+                case 25:
+                    break;
+                case 4: {
+                    sb = null;
+                    sb = new StringBuffer();
+                    yybegin(STRING_BEGIN);
+                }
+                case 26:
+                    break;
+                case 16: {
+                    sb.append('\b');
+                }
+                case 27:
+                    break;
+                case 6: {
+                    return new Yytoken(Yytoken.TYPE_RIGHT_BRACE, null);
+                }
+                case 28:
+                    break;
+                case 23: {
+                    Boolean val = Boolean.valueOf(yytext());
+                    return new Yytoken(Yytoken.TYPE_VALUE, val);
+                }
+                case 29:
+                    break;
+                case 22: {
+                    return new Yytoken(Yytoken.TYPE_VALUE, null);
+                }
+                case 30:
+                    break;
+                case 13: {
+                    yybegin(YYINITIAL);
+                    return new Yytoken(Yytoken.TYPE_VALUE, sb.toString());
+                }
+                case 31:
+                    break;
+                case 12: {
+                    sb.append('\\');
+                }
+                case 32:
+                    break;
+                case 21: {
+                    Double val = Double.valueOf(yytext());
+                    return new Yytoken(Yytoken.TYPE_VALUE, val);
+                }
+                case 33:
+                    break;
+                case 1: {
+                    throw new ParseException(yychar, ParseException.ERROR_UNEXPECTED_CHAR, Character.valueOf(yycharat(0)));
+                }
+                case 34:
+                    break;
+                case 8: {
+                    return new Yytoken(Yytoken.TYPE_RIGHT_SQUARE, null);
+                }
+                case 35:
+                    break;
+                case 19: {
+                    sb.append('\r');
+                }
+                case 36:
+                    break;
+                case 15: {
+                    sb.append('/');
+                }
+                case 37:
+                    break;
+                case 10: {
+                    return new Yytoken(Yytoken.TYPE_COLON, null);
+                }
+                case 38:
+                    break;
+                case 14: {
+                    sb.append('"');
+                }
+                case 39:
+                    break;
+                case 5: {
+                    return new Yytoken(Yytoken.TYPE_LEFT_BRACE, null);
+                }
+                case 40:
+                    break;
+                case 17: {
+                    sb.append('\f');
+                }
+                case 41:
+                    break;
+                case 24: {
+                    try {
+                        int ch = Integer.parseInt(yytext().substring(2), 16);
+                        sb.append((char) ch);
+                    } catch (Exception e) {
+                        throw new ParseException(yychar, ParseException.ERROR_UNEXPECTED_EXCEPTION, e);
+                    }
+                }
+                case 42:
+                    break;
+                case 20: {
+                    sb.append('\t');
+                }
+                case 43:
+                    break;
+                case 7: {
+                    return new Yytoken(Yytoken.TYPE_LEFT_SQUARE, null);
+                }
+                case 44:
+                    break;
+                case 2: {
+                    Long val = Long.valueOf(yytext());
+                    return new Yytoken(Yytoken.TYPE_VALUE, val);
+                }
+                case 45:
+                    break;
+                case 18: {
+                    sb.append('\n');
+                }
+                case 46:
+                    break;
+                case 9: {
+                    return new Yytoken(Yytoken.TYPE_COMMA, null);
+                }
+                case 47:
+                    break;
+                case 3: {
+                }
+                case 48:
+                    break;
+                default:
+                    if (zzInput == YYEOF && zzStartRead == zzCurrentPos) {
+                        zzAtEOF = true;
+                        return null;
+                    } else {
+                        zzScanError(ZZ_NO_MATCH);
+                    }
+            }
+        }
+    }
+
+}

client/src/main/java/com/alibaba/nacos/client/logger/json/parser/Yytoken.java

@@ -0,0 +1,81 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * $Id: Yytoken.java,v 1.1 2006/04/15 14:10:48 platform Exp $
+ * Created on 2006-4-15
+ */
+package com.alibaba.nacos.client.logger.json.parser;
+
+/**
+ * @author FangYidong<fangyidong@yahoo.com.cn>
+ */
+public class Yytoken {
+	/**
+	 * JSON primitive value: string,number,boolean,null
+	 */
+	public static final int TYPE_VALUE=0;
+	public static final int TYPE_LEFT_BRACE=1;
+	public static final int TYPE_RIGHT_BRACE=2;
+	public static final int TYPE_LEFT_SQUARE=3;
+	public static final int TYPE_RIGHT_SQUARE=4;
+	public static final int TYPE_COMMA=5;
+	public static final int TYPE_COLON=6;
+	/**
+	 * end of file
+	 */
+	public static final int TYPE_EOF=-1;
+	
+	public int type=0;
+	public Object value=null;
+	
+	public Yytoken(int type,Object value){
+		this.type=type;
+		this.value=value;
+	}
+	
+	public String toString(){
+		StringBuffer sb = new StringBuffer();
+		switch(type){
+		case TYPE_VALUE:
+			sb.append("VALUE(").append(value).append(")");
+			break;
+		case TYPE_LEFT_BRACE:
+			sb.append("LEFT BRACE({)");
+			break;
+		case TYPE_RIGHT_BRACE:
+			sb.append("RIGHT BRACE(})");
+			break;
+		case TYPE_LEFT_SQUARE:
+			sb.append("LEFT SQUARE([)");
+			break;
+		case TYPE_RIGHT_SQUARE:
+			sb.append("RIGHT SQUARE(])");
+			break;
+		case TYPE_COMMA:
+			sb.append("COMMA(,)");
+			break;
+		case TYPE_COLON:
+			sb.append("COLON(:)");
+			break;
+		case TYPE_EOF:
+			sb.append("END OF FILE");
+			break;
+		default:
+			break;
+		}
+		return sb.toString();
+	}
+}

client/src/main/java/com/alibaba/nacos/client/logger/log4j/Log4jLogger.java

@@ -0,0 +1,146 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.log4j;
+
+import org.apache.log4j.Level;
+
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.option.Log4jActivateOption;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+import com.alibaba.nacos.client.logger.support.LoggerSupport;
+import com.alibaba.nacos.client.logger.util.MessageUtil;
+
+
+/**
+ * Log4jLogger
+ * @author Nacos
+ *
+ */
+public class Log4jLogger extends LoggerSupport implements Logger {
+
+    private org.apache.log4j.Logger delegate;
+
+    public Log4jLogger(org.apache.log4j.Logger delegate) {
+        super(delegate);
+
+        if (delegate == null) {
+            throw new IllegalArgumentException("delegate Logger is null");
+        }
+        this.delegate = delegate;
+
+        this.activateOption = new Log4jActivateOption(delegate);
+    }
+
+    @Override
+    public void debug(String context, String message) {
+        if (isDebugEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.debug(MessageUtil.getMessage(context, message));
+        }
+    }
+
+    @Override
+    public void debug(String context, String format, Object... args) {
+        if (isDebugEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.debug(MessageUtil.getMessage(context, MessageUtil.formatMessage(format, args)));
+        }
+    }
+
+    @Override
+    public void info(String context, String message) {
+        if (isInfoEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.info(MessageUtil.getMessage(context, message));
+        }
+    }
+
+    @Override
+    public void info(String context, String format, Object... args) {
+        if (isInfoEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.info(MessageUtil.getMessage(context, MessageUtil.formatMessage(format, args)));
+        }
+    }
+
+    @Override
+    public void warn(String message, Throwable t) {
+        if (isWarnEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.warn(MessageUtil.getMessage(null, message), t);
+        }
+    }
+
+    @Override
+    public void warn(String context, String message) {
+        if (isWarnEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.warn(MessageUtil.getMessage(context, message));
+        }
+    }
+
+    @Override
+    public void warn(String context, String format, Object... args) {
+        if (isWarnEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.warn(MessageUtil.getMessage(context, MessageUtil.formatMessage(format, args)));
+        }
+    }
+
+    @Override
+    public void error(String context, String errorCode, String message) {
+        if (isErrorEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.error(MessageUtil.getMessage(context, errorCode, message));
+        }
+    }
+
+    @Override
+    public void error(String context, String errorCode, String message, Throwable t) {
+        if (isErrorEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.error(MessageUtil.getMessage(context, errorCode, message), t);
+        }
+    }
+
+    @Override
+    public void error(String context, String errorCode, String format, Object... args) {
+        if (isErrorEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.error(MessageUtil.getMessage(context, errorCode, MessageUtil.formatMessage(format, args)));
+        }
+    }
+
+    @Override
+    public boolean isDebugEnabled() {
+        return delegate.isDebugEnabled();
+    }
+
+    @Override
+    public boolean isInfoEnabled() {
+        return delegate.isInfoEnabled();
+    }
+
+    @Override
+    public boolean isWarnEnabled() {
+        return delegate.isEnabledFor(Level.WARN);
+    }
+
+    @Override
+    public boolean isErrorEnabled() {
+        return delegate.isEnabledFor(Level.ERROR);
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/log4j/Log4jLoggerFactory.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.log4j;
+
+import org.apache.log4j.LogManager;
+
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.nop.NopLogger;
+import com.alibaba.nacos.client.logger.support.ILoggerFactory;
+import com.alibaba.nacos.client.logger.support.LogLog;
+
+/**
+ * Log4jLogger Factory
+ * @author Nacos
+ *
+ */
+public class Log4jLoggerFactory implements ILoggerFactory {
+
+    public Log4jLoggerFactory() throws ClassNotFoundException {
+        Class.forName("org.apache.log4j.Level");
+    }
+
+    public Logger getLogger(Class<?> clazz) {
+        try {
+            return new Log4jLogger(LogManager.getLogger(clazz));
+        } catch (Throwable t) {
+            LogLog.error("Failed to get Log4jLogger", t);
+            return new NopLogger();
+        }
+    }
+
+    public Logger getLogger(String name) {
+        try {
+            return new Log4jLogger(LogManager.getLogger(name));
+        } catch (Throwable t) {
+            LogLog.error("Failed to get Log4jLogger", t);
+            return new NopLogger();
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/log4j2/Log4j2Logger.java

@@ -0,0 +1,144 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.log4j2;
+
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.option.Log4j2ActivateOption;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+import com.alibaba.nacos.client.logger.support.LoggerSupport;
+import com.alibaba.nacos.client.logger.util.MessageUtil;
+
+
+/**
+ * Log4j2Logger
+ * @author Nacos
+ *
+ */
+public class Log4j2Logger extends LoggerSupport implements Logger {
+
+    private org.apache.logging.log4j.Logger delegate;
+
+    public Log4j2Logger(org.apache.logging.log4j.Logger delegate) {
+        super(delegate);
+
+        if (delegate == null) {
+            throw new IllegalArgumentException("delegate Logger is null");
+        }
+        this.delegate = delegate;
+
+        this.activateOption = new Log4j2ActivateOption(delegate);
+    }
+
+    @Override
+    public void debug(String context, String message) {
+        if (isDebugEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.debug(MessageUtil.getMessage(context, message));
+        }
+    }
+
+    @Override
+    public void debug(String context, String format, Object... args) {
+        if (isDebugEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.debug(MessageUtil.getMessage(context, MessageUtil.formatMessage(format, args)));
+        }
+    }
+
+    @Override
+    public void info(String context, String message) {
+        if (isInfoEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.info(MessageUtil.getMessage(context, message));
+        }
+    }
+
+    @Override
+    public void info(String context, String format, Object... args) {
+        if (isInfoEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.info(MessageUtil.getMessage(context, MessageUtil.formatMessage(format, args)));
+        }
+    }
+
+    @Override
+    public void warn(String message, Throwable t) {
+        if (isWarnEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.warn(MessageUtil.getMessage(null, message), t);
+        }
+    }
+
+    @Override
+    public void warn(String context, String message) {
+        if (isWarnEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.warn(MessageUtil.getMessage(context, message));
+        }
+    }
+
+    @Override
+    public void warn(String context, String format, Object... args) {
+        if (isWarnEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.warn(MessageUtil.getMessage(context, MessageUtil.formatMessage(format, args)));
+        }
+    }
+
+    @Override
+    public void error(String context, String errorCode, String message) {
+        if (isErrorEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.error(MessageUtil.getMessage(context, errorCode, message));
+        }
+    }
+
+    @Override
+    public void error(String context, String errorCode, String message, Throwable t) {
+        if (isErrorEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.error(MessageUtil.getMessage(context, errorCode, message), t);
+        }
+    }
+
+    @Override
+    public void error(String context, String errorCode, String format, Object... args) {
+        if (isErrorEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.error(MessageUtil.getMessage(context, errorCode, MessageUtil.formatMessage(format, args)));
+        }
+    }
+
+    @Override
+    public boolean isDebugEnabled() {
+        return delegate.isDebugEnabled();
+    }
+
+    @Override
+    public boolean isInfoEnabled() {
+        return delegate.isInfoEnabled();
+    }
+
+    @Override
+    public boolean isWarnEnabled() {
+        return delegate.isWarnEnabled();
+    }
+
+    @Override
+    public boolean isErrorEnabled() {
+        return delegate.isErrorEnabled();
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/log4j2/Log4j2LoggerFactory.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.log4j2;
+
+import org.apache.logging.log4j.LogManager;
+
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.nop.NopLogger;
+import com.alibaba.nacos.client.logger.support.ILoggerFactory;
+import com.alibaba.nacos.client.logger.support.LogLog;
+
+/**
+ * Log4j2Logger Factory
+ * @author Nacos
+ *
+ */
+public class Log4j2LoggerFactory implements ILoggerFactory {
+
+    public Log4j2LoggerFactory() throws ClassNotFoundException {
+        Class.forName("org.apache.logging.log4j.core.Logger");
+    }
+
+    @Override
+    public Logger getLogger(Class<?> clazz) {
+        try {
+            return new Log4j2Logger(LogManager.getLogger(clazz));
+        } catch (Throwable t) {
+            LogLog.error("Failed to get Log4j2Logger", t);
+            return new NopLogger();
+        }
+    }
+
+    @Override
+    public Logger getLogger(String name) {
+        try {
+            return new Log4j2Logger(LogManager.getLogger(name));
+        } catch (Throwable t) {
+            LogLog.error("Failed to get Log4j2Logger", t);
+            return new NopLogger();
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/nop/NopLogger.java

@@ -0,0 +1,99 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.nop;
+
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.support.LoggerSupport;
+/**
+ * NopLogger
+ * @author Nacos
+ *
+ */
+public class NopLogger extends LoggerSupport implements Logger {
+
+    public NopLogger(){
+        super(null);
+    }
+
+    @Override
+    public void debug(String context, String message) {
+
+    }
+
+    @Override
+    public void debug(String context, String format, Object... args) {
+
+    }
+
+    @Override
+    public void info(String context, String message) {
+
+    }
+
+    @Override
+    public void info(String context, String format, Object... args) {
+
+    }
+
+    public void warn(String message, Throwable t) {
+
+    }
+
+    @Override
+    public void warn(String context, String message) {
+
+    }
+
+    @Override
+    public void warn(String context, String format, Object... args) {
+
+    }
+
+    @Override
+    public void error(String context, String errorCode, String message) {
+
+    }
+
+    @Override
+    public void error(String context, String errorCode, String message, Throwable t) {
+
+    }
+
+    @Override
+    public void error(String context, String errorCode, String format, Object... args) {
+
+    }
+
+    @Override
+    public boolean isDebugEnabled() {
+        return false;
+    }
+
+    @Override
+    public boolean isInfoEnabled() {
+        return false;
+    }
+
+    @Override
+    public boolean isWarnEnabled() {
+        return false;
+    }
+
+    @Override
+    public boolean isErrorEnabled() {
+        return false;
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/nop/NopLoggerFactory.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.nop;
+
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.support.ILoggerFactory;
+/**
+ * NopLogger Factory
+ * @author Nacos
+ *
+ */
+public class NopLoggerFactory implements ILoggerFactory {
+
+    @Override
+    public Logger getLogger(Class<?> clazz) {
+        return new NopLogger();
+    }
+
+    @Override
+    public Logger getLogger(String name) {
+        return new NopLogger();
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/option/AbstractActiveOption.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.option;
+
+import org.apache.log4j.AsyncAppender;
+
+import com.alibaba.nacos.client.logger.Level;
+import com.alibaba.nacos.client.logger.support.LogLog;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.List;
+
+/**
+ * AbstractActiveOption
+ * @author Nacos
+ *
+ */
+public abstract class AbstractActiveOption implements ActivateOption {
+
+    protected String productName;
+    protected Level level;
+
+    @Override
+    public String getProductName() {
+        return productName;
+    }
+
+    @Override
+    public Level getLevel() {
+        return level;
+    }
+
+    protected void setProductName(String productName) {
+        if (this.productName == null && productName != null) {
+            this.productName = productName;
+        }
+    }
+
+    public static void invokeMethod(Object object, List<Object[]> args) {
+        if (args != null && object != null) {
+            for (Object[] arg : args) {
+                if (arg != null && arg.length == 3) {
+                    try {
+                        Method m = object.getClass().getMethod((String) arg[0], (Class<?>[]) arg[1]);
+                        m.invoke(object, arg[2]);
+                    } catch (NoSuchMethodException e) {
+                        LogLog.info("Can't find method for " + object.getClass() + " " + arg[0] + " " + arg[2]);
+                    } catch (IllegalAccessException e) {
+                        LogLog.info("Can't invoke method for " + object.getClass() + " " + arg[0] + " " + arg[2]);
+                    } catch (InvocationTargetException e) {
+                        LogLog.info("Can't invoke method for " + object.getClass() + " " + arg[0] + " " + arg[2]);
+                    } catch (Throwable t) {
+                        LogLog.info("Can't invoke method for " + object.getClass() + " " + arg[0] + " " + arg[2]);
+                    }
+                }
+            }
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/option/ActivateOption.java

@@ -0,0 +1,195 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.option;
+
+import java.util.List;
+import java.util.Map;
+
+import com.alibaba.nacos.client.logger.Level;
+import com.alibaba.nacos.client.logger.Logger;
+
+/**
+ * <pre>
+ * 激活Logger的选项，包括：
+ * Appender/Layout
+ * Level
+ * Additivity
+ * Aysnc
+ * 请参考具体的实现逻辑
+ * </pre>
+ *
+ * @author zhuyong 2014年3月20日 上午10:20:51
+ */
+public interface ActivateOption {
+
+    /**
+     * 设置ConsoleAppender，生产环境慎用
+     *
+     * @param target   System.out or System.err
+     * @param encoding 编码
+     */
+    void activateConsoleAppender(String target, String encoding);
+
+    /**
+     * 设置FileAppender，日志按天回滚
+     *
+     * @param productName 中间件产品名，如hsf, tddl
+     * @param file        日志文件名，如hsf.log，支持子目录，如client/hsf.log
+     * @param encoding    编码
+     */
+    void activateAppender(String productName, String file, String encoding);
+
+    /**
+     * 设置AsyncAppender，内嵌DailyRollingFileAppender，日志按天回滚，参考 {@link ActivateOption#activateAsync(int, int)}
+     *
+     * @param productName 中间件产品名，如hsf, tddl
+     * @param file        日志文件名，如hsf.log，支持子目录，如client/hsf.log
+     * @param encoding    编码
+     */
+    @Deprecated
+    void activateAsyncAppender(String productName, String file, String encoding);
+
+    /**
+     * 设置AsyncAppender，内嵌DailyRollingFileAppender，日志按天回滚，参考 {@link ActivateOption#activateAsync(int, int)}
+     *
+     * @param productName         中间件产品名，如hsf, tddl
+     * @param file                日志文件名，如hsf.log，支持子目录，如client/hsf.log
+     * @param encoding            编码
+     * @param queueSize           等待队列大小
+     * @param discardingThreshold discardingThreshold，该参数仅对logback实现有效，log4j和log4j2无效
+     */
+    @Deprecated
+    void activateAsyncAppender(String productName, String file, String encoding, int queueSize,
+                               int discardingThreshold);
+
+    /**
+     * 设置按天和文件大小回滚
+     *
+     * @param productName 中间件产品名，如hsf, tddl
+     * @param file        日志文件名，如hsf.log，支持子目录，如client/hsf.log
+     * @param encoding    编码
+     * @param size        文件大小，如300MB，支持KB，MB，GB，该参数对log4j实现不生效，log4j2和logback有效
+     */
+    void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size);
+
+    /**
+     * <pre>
+     * 设置按日期格式和文件大小回滚
+     * 说明：Log4j 对日期格式不生效，只有按大小回滚，同时不支持备份文件，即达到文件大小直接截断，如果需要备份文件，请参考带 maxBackupIndex 参数的方法
+     * </pre>
+     *
+     * @param productName 中间件产品名，如hsf, tddl
+     * @param file        日志文件名，如hsf.log，支持子目录，如client/hsf.log
+     * @param encoding    编码
+     * @param size        文件大小，如300MB，支持KB，MB，GB
+     * @param datePattern 日期格式，如yyyy-MM-dd 或 yyyy-MM，请自行保证格式正确，该参数对log4j实现不生效，log4j2和logback有效
+     */
+    void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size,
+                                                String datePattern);
+
+    /**
+     * <pre>
+     * 设置按日期格式、文件大小、最大备份文件数回滚
+     * 说明：
+     * 1、Log4j 对日期格式不生效，只有按大小、备份文件数回滚，备份文件数 maxBackupIndex 参数必须是 >= 0 的整数，为0时表示直接截断，不备份
+     * 2、备份日志格式说明：
+     *     Log4j：notify.log.1, notify.log.2，即备份文件以 .1 .2结尾，序号从1开始
+     *     Logback: notify.log.2014-09-19.0， notify.log.2014-09-19.1，即中间会带日期格式，同时序号从0开始
+     * </pre>
+     *
+     * @param productName    中间件产品名，如hsf, tddl
+     * @param file           日志文件名，如hsf.log，支持子目录，如client/hsf.log
+     * @param encoding       编码
+     * @param size           文件大小，如300MB，支持KB，MB，GB
+     * @param datePattern    日期格式，如yyyy-MM-dd 或 yyyy-MM，请自行保证格式正确，该参数对log4j实现不生效，log4j2和logback有效
+     * @param maxBackupIndex 最大备份文件数，如10（对于 Logback，则是保留10天的文件，但是这10天内的文件则会按大小回滚）
+     */
+    void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size,
+                                                String datePattern, int maxBackupIndex);
+
+    /**
+     * <pre>
+     * 设置按文件大小、最大备份文件数回滚
+     * 说明：
+     * 1、Log4j 备份文件数 maxBackupIndex 参数必须是 >= 0 的整数，为0时表示直接截断，不备份
+     * 2、备份日志格式说明：
+     *     Log4j：notify.log.1, notify.log.2，即备份文件以 .1 .2结尾，序号从1开始
+     *     Logback: notify.log.1， notify.log.1
+     * </pre>
+     *
+     * @param productName    中间件产品名，如hsf, tddl
+     * @param file           日志文件名，如hsf.log，支持子目录，如client/hsf.log
+     * @param encoding       编码
+     * @param size           文件大小，如300MB，支持KB，MB，GB
+     * @param maxBackupIndex 最大备份文件数，如10
+     */
+    void activateAppenderWithSizeRolling(String productName, String file, String encoding, String size,
+                                         int maxBackupIndex);
+
+    /**
+     * 将当前logger对象的appender设置为异步Appender
+     * 注意：此logger需要提前进行Appender的初始化
+     *
+     * @param queueSize           等待队列大小
+     * @param discardingThreshold discardingThreshold，该参数仅对logback实现有效，log4j和log4j2无效
+     * @since 0.2.2
+     */
+    void activateAsync(int queueSize, int discardingThreshold);
+
+    /**
+     * 将当前logger对象的appender设置为异步Appender
+     * 注意：此logger需要提前进行Appender的初始化
+     *
+     * @param args AsyncAppender配置参数，请自行保证参数的正确性，要求每个Object[]有3个元素，第一个为set方法名，第二个为方法类型数组，第三个为对应的参数值，如
+     *             args.add(new Object[] { "setBufferSize", new Class<?>[] { int.class }, queueSize });
+     * @since 0.2.3
+     */
+    void activateAsync(List<Object[]> args);
+
+    /**
+     * 使用logger对象的appender来初始化当前logger
+     *
+     * @param logger
+     */
+    void activateAppender(Logger logger);
+
+    /**
+     * 设置日志级别
+     *
+     * @param level 日志级别
+     * @see Level
+     */
+    void setLevel(Level level);
+
+    /**
+     * 获取日志级别
+     * @return level
+     */
+    Level getLevel();
+
+    /**
+     * 设置日志是否Attach到Parent
+     *
+     * @param additivity true or false
+     */
+    void setAdditivity(boolean additivity);
+
+    /**
+     * 获取所属的产品名
+     * @return 所属的产品名
+     */
+    String getProductName();
+}

client/src/main/java/com/alibaba/nacos/client/logger/option/Log4j2ActivateOption.java

@@ -0,0 +1,274 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.option;
+
+import org.apache.logging.log4j.core.Appender;
+import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.appender.AsyncAppender;
+import org.apache.logging.log4j.core.appender.ConsoleAppender;
+import org.apache.logging.log4j.core.appender.RollingFileAppender;
+import org.apache.logging.log4j.core.appender.rolling.*;
+import org.apache.logging.log4j.core.async.ArrayBlockingQueueFactory;
+import org.apache.logging.log4j.core.config.AppenderRef;
+import org.apache.logging.log4j.core.config.Configuration;
+
+import com.alibaba.nacos.client.logger.Level;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+
+import java.io.File;
+import java.nio.charset.Charset;
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * @author zhuyong on 2017/4/13.
+ */
+public class Log4j2ActivateOption extends AbstractActiveOption {
+
+    protected org.apache.logging.log4j.core.Logger logger;
+    protected Configuration configuration;
+
+    public Log4j2ActivateOption(org.apache.logging.log4j.Logger logger) {
+        if (logger != null) {
+            if (logger instanceof org.apache.logging.log4j.core.Logger) {
+                this.logger = (org.apache.logging.log4j.core.Logger) logger;
+
+                configuration = this.logger.getContext().getConfiguration();
+            } else {
+                throw new RuntimeException("logger must instanceof org.apache.logging.log4j.core.Logger, " + logger.getClass().getName());
+            }
+        }
+    }
+
+    @Override
+    public void activateConsoleAppender(String target, String encoding) {
+        org.apache.logging.log4j.core.Layout layout = org.apache.logging.log4j.core.layout.PatternLayout.newBuilder().
+                withConfiguration(configuration)
+                .withPattern(LoggerHelper.getPattern())
+                .withCharset(Charset.forName(encoding))
+                .build();
+        org.apache.logging.log4j.core.appender.ConsoleAppender appender = ConsoleAppender.createAppender(layout, null,
+                ConsoleAppender.Target.valueOf(target.toUpperCase().replace(".", "_")), "LoggerApiConsoleAppender", false, false, true);
+        appender.start();
+        removeAllAppenders(logger);
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAppender(String productName, String file, String encoding) {
+        org.apache.logging.log4j.core.appender.RollingFileAppender appender = RollingFileAppender.newBuilder()
+                .withName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender")
+                .withFileName(LoggerHelper.getLogFileP(productName, file))
+                .withAppend(true)
+                .withBufferedIo(true)
+                .setConfiguration(configuration)
+                .withFilePattern(LoggerHelper.getLogFile(productName, file) + ".%d{yyyy-MM-dd}")
+                .withLayout(buildLayout(encoding))
+                .withCreateOnDemand(false)
+                .withPolicy(TimeBasedTriggeringPolicy.createPolicy("1", "true"))
+                .withStrategy(DefaultRolloverStrategy.createStrategy(null, null, "nomax", null, null, false, configuration))
+                .build();
+
+        appender.start();
+        removeAllAppenders(logger);
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAsyncAppender(String productName, String file, String encoding) {
+        activateAsyncAppender(productName, file, encoding, Integer.MIN_VALUE, Integer.MIN_VALUE);
+    }
+
+    @Override
+    public void activateAsyncAppender(String productName, String file, String encoding, int queueSize, int discardingThreshold) {
+        activateAppender(productName, file, encoding);
+        activateAsync(queueSize, discardingThreshold);
+    }
+
+    @Override
+    public void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size) {
+        activateAppenderWithTimeAndSizeRolling(productName, file, encoding, size, "yyyy-MM-dd");
+    }
+
+    @Override
+    public void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size, String datePattern) {
+        org.apache.logging.log4j.core.appender.RollingFileAppender appender = RollingFileAppender.newBuilder()
+                .withName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender")
+                .withFileName(LoggerHelper.getLogFileP(productName, file))
+                .withAppend(true)
+                .withBufferedIo(true)
+                .setConfiguration(configuration)
+                .withFilePattern(LoggerHelper.getLogFile(productName, file) + ".%d{" + datePattern + "}")
+                .withLayout(buildLayout(encoding))
+                .withCreateOnDemand(false)
+                .withPolicy(CompositeTriggeringPolicy.createPolicy(TimeBasedTriggeringPolicy.createPolicy("1", "true"), SizeBasedTriggeringPolicy.createPolicy(size)))
+                .withStrategy(DefaultRolloverStrategy.createStrategy(null, null, "nomax", null, null, false, configuration))
+                .build();
+
+        appender.start();
+        removeAllAppenders(logger);
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size, String datePattern, int maxBackupIndex) {
+        org.apache.logging.log4j.core.appender.RollingFileAppender appender = RollingFileAppender.newBuilder()
+                .withName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender")
+                .withFileName(LoggerHelper.getLogFileP(productName, file))
+                .withAppend(true)
+                .withBufferedIo(true)
+                .setConfiguration(configuration)
+                .withFilePattern(LoggerHelper.getLogFile(productName, file) + ".%d{" + datePattern + "}.%i")
+                .withLayout(buildLayout(encoding))
+                .withCreateOnDemand(false)
+                .withPolicy(CompositeTriggeringPolicy.createPolicy(TimeBasedTriggeringPolicy.createPolicy("1", "true"), SizeBasedTriggeringPolicy.createPolicy(size)))
+                .withStrategy(DefaultRolloverStrategy.createStrategy(String.valueOf(maxBackupIndex), "1", "max", null, null, false, configuration))
+                .build();
+
+        appender.start();
+        removeAllAppenders(logger);
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAppenderWithSizeRolling(String productName, String file, String encoding, String size, int maxBackupIndex) {
+        org.apache.logging.log4j.core.appender.RollingFileAppender appender = RollingFileAppender.newBuilder()
+                .withName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender")
+                .withFileName(LoggerHelper.getLogFileP(productName, file))
+                .withAppend(true)
+                .withBufferedIo(true)
+                .setConfiguration(configuration)
+                .withFilePattern(LoggerHelper.getLogFile(productName, file) + ".%i")
+                .withLayout(buildLayout(encoding))
+                .withCreateOnDemand(false)
+                .withPolicy(SizeBasedTriggeringPolicy.createPolicy(size))
+                .withStrategy(DefaultRolloverStrategy.createStrategy(String.valueOf(maxBackupIndex), "1", "max", null, null, false, configuration))
+                .build();
+
+        appender.start();
+        removeAllAppenders(logger);
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAsync(int queueSize, int discardingThreshold) {
+        List<Object[]> args = new ArrayList<Object[]>();
+
+        if (queueSize != Integer.MIN_VALUE) {
+            args.add(new Object[] { "setBufferSize", new Class<?>[] { int.class }, queueSize });
+        }
+        activateAsync(args);
+    }
+
+    @Override
+    public void activateAsync(List<Object[]> args) {
+        Map<String, Appender> appenders = logger.getAppenders();
+        if (appenders == null) {
+            throw new IllegalStateException("Activate async appender failed, no appender exist.");
+        }
+
+        AppenderRef[] refs = new AppenderRef[appenders.size()];
+        int i = 0;
+        for (Appender appender : appenders.values()) {
+            configuration.addAppender(appender);
+            refs[i++] = AppenderRef.createAppenderRef(appender.getName(), null, null);
+        }
+
+        AsyncAppender.Builder builder = AsyncAppender.newBuilder()
+                                                     .setName(productName + "." + logger.getName() + ".AsyncAppender")
+                                                     .setConfiguration(configuration)
+                                                     .setAppenderRefs(refs)
+                                                     .setBlockingQueueFactory(ArrayBlockingQueueFactory.<LogEvent>createFactory());
+
+        invokeMethod(builder, args);
+
+        AsyncAppender asyncAppender = builder.build();
+        asyncAppender.start();
+
+        removeAllAppenders(logger);
+        logger.addAppender(asyncAppender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAppender(Logger logger) {
+        if (!(logger.getDelegate() instanceof org.apache.logging.log4j.core.Logger)) {
+            throw new IllegalArgumentException("logger must be org.apache.logging.log4j.core.Logger, but it's "
+                    + logger.getDelegate().getClass());
+        }
+
+        activateAppender(((org.apache.logging.log4j.core.Logger) logger.getDelegate()));
+
+        setProductName(logger.getProductName());
+    }
+
+    protected void activateAppender(org.apache.logging.log4j.core.Logger logger) {
+        removeAllAppenders(this.logger);
+
+        Map<String, Appender> appenders = null;
+        if ((appenders = logger.getAppenders()) != null) {
+            for (Appender appender : appenders.values()) {
+                this.logger.addAppender(appender);
+            }
+        }
+    }
+
+    @Override
+    public void setLevel(Level level) {
+        this.level = level;
+
+        org.apache.logging.log4j.Level l = org.apache.logging.log4j.Level.toLevel(level.getName(), org.apache.logging.log4j.Level.ERROR);
+        logger.setLevel(l);
+        logger.getContext().getConfiguration().getLoggerConfig(this.logger.getName()).setLevel(l);
+    }
+
+    @Override
+    public void setAdditivity(boolean additivity) {
+        logger.setAdditive(additivity);
+    }
+
+    protected org.apache.logging.log4j.core.Layout buildLayout(String encoding) {
+        org.apache.logging.log4j.core.Layout layout = org.apache.logging.log4j.core.layout.PatternLayout.newBuilder().
+                withConfiguration(configuration)
+                .withPattern(LoggerHelper.getPattern())
+                .withCharset(Charset.forName(encoding))
+                .build();
+        return layout;
+    }
+
+    protected void removeAllAppenders(org.apache.logging.log4j.core.Logger logger) {
+        Map<String, Appender> appenders = logger.getAppenders();
+        if (appenders != null) {
+            for (Appender appender : appenders.values()) {
+                logger.removeAppender(appender);
+            }
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/option/Log4jActivateOption.java

@@ -0,0 +1,212 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.option;
+
+import org.apache.log4j.*;
+
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+
+import java.io.File;
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * ActivateOption的Log4j实现
+ *
+ * @author zhuyong 2014年3月20日 上午10:24:36
+ */
+public class Log4jActivateOption extends AbstractActiveOption {
+
+    protected org.apache.log4j.Logger logger;
+
+    public Log4jActivateOption(org.apache.log4j.Logger logger) {
+        this.logger = logger;
+    }
+
+    @Override
+    public void activateConsoleAppender(String target, String encoding) {
+        org.apache.log4j.ConsoleAppender appender = new org.apache.log4j.ConsoleAppender();
+        appender.setLayout(new PatternLayout(LoggerHelper.getPattern()));
+        appender.setTarget(target);
+        appender.setEncoding(encoding);
+        appender.activateOptions();
+
+        logger.removeAllAppenders();
+        logger.addAppender(appender);
+    }
+
+    @Override
+    public void activateAppender(String productName, String file, String encoding) {
+        org.apache.log4j.Appender appender = getLog4jDailyRollingFileAppender(productName, file, encoding);
+        logger.removeAllAppenders();
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAsyncAppender(String productName, String file, String encoding) {
+        activateAsyncAppender(productName, file, encoding, Integer.MIN_VALUE, Integer.MIN_VALUE);
+    }
+
+    @Override
+    public void activateAsyncAppender(String productName, String file, String encoding, int queueSize,
+                                      int discardingThreshold) {
+        activateAppender(productName, file, encoding);
+        activateAsync(queueSize, discardingThreshold);
+    }
+
+    @Override
+    public void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size) {
+        activateAppender(productName, file, encoding);
+    }
+
+    @Override
+    public void setLevel(com.alibaba.nacos.client.logger.Level level) {
+        this.level = level;
+        logger.setLevel(org.apache.log4j.Level.toLevel(level.getName()));
+    }
+
+    @Override
+    public void setAdditivity(boolean additivity) {
+        logger.setAdditivity(additivity);
+    }
+
+    protected org.apache.log4j.Appender getLog4jDailyRollingFileAppender(String productName, String file,
+                                                                         String encoding) {
+        DailyRollingFileAppender appender = new DailyRollingFileAppender();
+        appender.setName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender");
+        appender.setLayout(new PatternLayout(LoggerHelper.getPattern(productName)));
+        appender.setAppend(true);
+        appender.setFile(LoggerHelper.getLogFileP(productName, file));
+        appender.setEncoding(encoding);
+        appender.activateOptions();
+
+        return appender;
+    }
+
+    @Override
+    public void activateAppender(Logger logger) {
+        if (!(logger.getDelegate() instanceof org.apache.log4j.Logger)) {
+            throw new IllegalArgumentException(
+                    "logger must be org.apache.log4j.Logger, but it's " + logger.getDelegate().getClass());
+        }
+        activateAppender((org.apache.log4j.Logger) logger.getDelegate());
+
+        setProductName(logger.getProductName());
+    }
+
+    protected void activateAppender(org.apache.log4j.Logger logger) {
+        this.logger.removeAllAppenders();
+
+        Enumeration<?> enums = logger.getAllAppenders();
+        while (enums != null && enums.hasMoreElements()) {
+            this.logger.addAppender((Appender) enums.nextElement());
+        }
+    }
+
+    @Override
+    public void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size,
+                                                       String datePattern) {
+        Appender appender = getLog4jRollingFileAppender(productName, file, encoding, size, datePattern, -1);
+
+        logger.removeAllAppenders();
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size,
+                                                       String datePattern, int maxBackupIndex) {
+        Appender appender = getLog4jRollingFileAppender(productName, file, encoding, size, datePattern, maxBackupIndex);
+        logger.removeAllAppenders();
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    protected org.apache.log4j.Appender getLog4jRollingFileAppender(String productName, String file, String encoding,
+                                                                    String size, String datePattern,
+                                                                    int maxBackupIndex) {
+        RollingFileAppender appender = new RollingFileAppender();
+        appender.setName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender");
+        appender.setLayout(new PatternLayout(LoggerHelper.getPattern(productName)));
+        appender.setAppend(true);
+        appender.setFile(LoggerHelper.getLogFileP(productName, file));
+        appender.setEncoding(encoding);
+        appender.setMaxFileSize(size);
+        if (maxBackupIndex >= 0) {
+            // 等于0表示直接truck
+            appender.setMaxBackupIndex(maxBackupIndex);
+        }
+        appender.activateOptions();
+
+        return appender;
+    }
+
+    @Override
+    public void activateAppenderWithSizeRolling(String productName, String file, String encoding, String size,
+                                                int maxBackupIndex) {
+        Appender appender = getLog4jRollingFileAppender(productName, file, encoding, size, null, maxBackupIndex);
+        logger.removeAllAppenders();
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAsync(int queueSize, int discardingThreshold) {
+        // discardingThreshold is unused for log4j
+        List<Object[]> args = new ArrayList<Object[]>();
+
+        if (queueSize != Integer.MIN_VALUE) {
+            args.add(new Object[] { "setBufferSize", new Class<?>[] { int.class }, queueSize });
+        }
+        activateAsync(args);
+    }
+
+    @Override
+    public void activateAsync(List<Object[]> args) {
+        AsyncAppender asyncAppender = new AsyncAppender();
+
+        invokeMethod(asyncAppender, args);
+
+        asyncAppender.setName(productName + "." + logger.getName() + ".AsyncAppender");
+        Enumeration<Appender> appenders = logger.getAllAppenders();
+
+        if (appenders == null) {
+            throw new IllegalStateException("Activate async appender failed, no appender exist.");
+        }
+
+        while (appenders.hasMoreElements()) {
+            asyncAppender.addAppender(appenders.nextElement());
+        }
+
+        appenders = logger.getAllAppenders();
+        while (appenders.hasMoreElements()) {
+            logger.removeAppender(appenders.nextElement());
+        }
+
+        logger.addAppender(asyncAppender);
+
+        setProductName(productName);
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/option/Logback918ActivateOption.java

@@ -0,0 +1,334 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.option;
+
+import ch.qos.logback.classic.AsyncAppender;
+import ch.qos.logback.classic.PatternLayout;
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.Appender;
+import ch.qos.logback.core.rolling.*;
+import ch.qos.logback.core.util.FileSize;
+
+import java.io.File;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+import com.alibaba.nacos.client.logger.Level;
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.support.LogLog;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+
+/**
+ * logback 0.9.18版本及以前适用
+ *
+ * @author zhuyong 2014年3月20日 上午11:16:26
+ */
+@SuppressWarnings({ "rawtypes", "unchecked" })
+public class Logback918ActivateOption extends AbstractActiveOption {
+
+    private ch.qos.logback.classic.Logger logger;
+
+    public Logback918ActivateOption(Object logger) {
+        if (logger instanceof ch.qos.logback.classic.Logger) {
+            this.logger = (ch.qos.logback.classic.Logger) logger;
+        } else {
+            throw new IllegalArgumentException("logger must be instanceof ch.qos.logback.classic.Logger");
+        }
+    }
+
+    @Override
+    public void activateConsoleAppender(String target, String encoding) {
+        ch.qos.logback.core.ConsoleAppender appender = new ch.qos.logback.core.ConsoleAppender();
+        appender.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        appender.setTarget(target);
+        PatternLayout layout = new PatternLayout();
+        layout.setPattern(LoggerHelper.getPattern());
+        layout.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        layout.start();
+        appender.setLayout(layout);
+        appender.start();
+
+        logger.detachAndStopAllAppenders();
+        logger.addAppender(appender);
+    }
+
+    @Override
+    public void activateAppender(String productName, String file, String encoding) {
+        ch.qos.logback.core.Appender appender = getLogbackDailyRollingFileAppender(productName, file, encoding);
+        logger.detachAndStopAllAppenders();
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAsyncAppender(String productName, String file, String encoding) {
+        activateAsyncAppender(productName, file, encoding, Integer.MIN_VALUE, Integer.MIN_VALUE);
+    }
+
+    public void activateAsyncAppender(String productName, String file, String encoding, int queueSize,
+                                      int discardingThreshold) {
+        activateAppender(productName, file, encoding);
+        activateAsync(queueSize, discardingThreshold);
+    }
+
+    @Override
+    public void setLevel(Level level) {
+        this.level = level;
+        logger.setLevel(ch.qos.logback.classic.Level.valueOf(level.getName()));
+    }
+
+    @Override
+    public void setAdditivity(boolean additivity) {
+        logger.setAdditive(additivity);
+    }
+
+    @Override
+    public void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size) {
+        ch.qos.logback.core.Appender appender = getLogbackDailyAndSizeRollingFileAppender(productName, file, encoding,
+                                                                                          size);
+        logger.detachAndStopAllAppenders();
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    protected ch.qos.logback.core.Appender getLogbackDailyRollingFileAppender(String productName, String file,
+                                                                              String encoding) {
+        RollingFileAppender appender = new RollingFileAppender();
+        appender.setContext(LogbackLoggerContextUtil.getLoggerContext());
+
+        appender.setName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender");
+        appender.setAppend(true);
+        appender.setFile(LoggerHelper.getLogFile(productName, file));
+
+        TimeBasedRollingPolicy rolling = new TimeBasedRollingPolicy();
+        rolling.setParent(appender);
+        rolling.setFileNamePattern(LoggerHelper.getLogFile(productName, file) + ".%d{yyyy-MM-dd}");
+        rolling.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        rolling.start();
+        appender.setRollingPolicy(rolling);
+
+        PatternLayout layout = new PatternLayout();
+        layout.setPattern(LoggerHelper.getPattern(productName));
+        layout.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        layout.start();
+        appender.setLayout(layout);
+
+        // 启动
+        appender.start();
+
+        return appender;
+    }
+
+    protected ch.qos.logback.core.Appender getLogbackDailyAndSizeRollingFileAppender(String productName, String file,
+                                                                                     String encoding, String size) {
+        return getLogbackDailyAndSizeRollingFileAppender(productName, file, encoding, size, "yyyy-MM-dd", -1);
+    }
+
+    @Override
+    public void activateAppender(Logger logger) {
+        if (!(logger.getDelegate() instanceof ch.qos.logback.classic.Logger)) {
+            throw new IllegalArgumentException(
+                    "logger must be ch.qos.logback.classic.Logger, but it's " + logger.getDelegate().getClass());
+        }
+        this.logger.detachAndStopAllAppenders();
+
+        Iterator<ch.qos.logback.core.Appender<ILoggingEvent>> iter = ((ch.qos.logback.classic.Logger) logger.getDelegate()).iteratorForAppenders();
+        while (iter.hasNext()) {
+            ch.qos.logback.core.Appender<ILoggingEvent> appender = iter.next();
+            this.logger.addAppender(appender);
+        }
+    }
+
+    @Override
+    public void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size,
+                                                       String datePattern) {
+        ch.qos.logback.core.Appender appender = getLogbackDailyAndSizeRollingFileAppender(productName, file, encoding,
+                                                                                          size, datePattern, -1);
+        logger.detachAndStopAllAppenders();
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    protected ch.qos.logback.core.Appender getLogbackDailyAndSizeRollingFileAppender(String productName, String file,
+                                                                                     String encoding, String size,
+                                                                                     String datePattern,
+                                                                                     int maxBackupIndex) {
+        RollingFileAppender appender = new RollingFileAppender();
+        appender.setContext(LogbackLoggerContextUtil.getLoggerContext());
+
+        appender.setName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender");
+        appender.setAppend(true);
+        appender.setFile(LoggerHelper.getLogFile(productName, file));
+
+        TimeBasedRollingPolicy rolling = new TimeBasedRollingPolicy();
+        rolling.setParent(appender);
+        if (maxBackupIndex >= 0) {
+            rolling.setMaxHistory(maxBackupIndex);
+        }
+        rolling.setFileNamePattern(LoggerHelper.getLogFile(productName, file) + ".%d{" + datePattern + "}.%i");
+        rolling.setContext(LogbackLoggerContextUtil.getLoggerContext());
+
+        SizeAndTimeBasedFNATP fnatp = new SizeAndTimeBasedFNATP();
+        setMaxFileSize(fnatp, size);
+        fnatp.setTimeBasedRollingPolicy(rolling);
+        rolling.setTimeBasedFileNamingAndTriggeringPolicy(fnatp);
+
+        rolling.start();
+        appender.setRollingPolicy(rolling);
+
+        PatternLayout layout = new PatternLayout();
+        layout.setPattern(LoggerHelper.getPattern(productName));
+        layout.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        layout.start();
+        appender.setLayout(layout);
+
+        // 启动
+        appender.start();
+
+        return appender;
+    }
+
+    @Override
+    public void activateAppenderWithTimeAndSizeRolling(String productName, String file, String encoding, String size,
+                                                       String datePattern, int maxBackupIndex) {
+        ch.qos.logback.core.Appender appender = getLogbackDailyAndSizeRollingFileAppender(productName, file, encoding,
+                                                                                          size, datePattern,
+                                                                                          maxBackupIndex);
+        logger.detachAndStopAllAppenders();
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAppenderWithSizeRolling(String productName, String file, String encoding, String size,
+                                                int maxBackupIndex) {
+        ch.qos.logback.core.Appender appender = getSizeRollingAppender(productName, file, encoding, size,
+                                                                       maxBackupIndex);
+        logger.detachAndStopAllAppenders();
+        logger.addAppender(appender);
+
+        setProductName(productName);
+    }
+
+    @Override
+    public void activateAsync(int queueSize, int discardingThreshold) {
+        List<Object[]> args = new ArrayList<Object[]>();
+
+        if (queueSize != Integer.MIN_VALUE) {
+            args.add(new Object[] { "setQueueSize", new Class<?>[] { int.class }, queueSize });
+        }
+
+        if (discardingThreshold != Integer.MIN_VALUE) {
+            args.add(new Object[] { "setDiscardingThreshold", new Class<?>[] { int.class }, discardingThreshold });
+        }
+
+        activateAsync(args);
+    }
+
+    @Override
+    public void activateAsync(List<Object[]> args) {
+        AsyncAppender asynAppender = new AsyncAppender();
+
+        invokeMethod(asynAppender, args);
+
+        asynAppender.setName(productName + "." + logger.getName() + ".AsyncAppender");
+        asynAppender.setContext(LogbackLoggerContextUtil.getLoggerContext());
+
+        Iterator<Appender<ILoggingEvent>> iterator = logger.iteratorForAppenders();
+        boolean hasAppender = false;
+        while (iterator.hasNext()) {
+            hasAppender = true;
+            asynAppender.addAppender(iterator.next());
+        }
+
+        if (!hasAppender) {
+            throw new IllegalStateException("Activate async appender failed, no appender exist.");
+        }
+
+        asynAppender.start();
+
+        iterator = logger.iteratorForAppenders();
+        while (iterator.hasNext()) {
+            logger.detachAppender(iterator.next());
+        }
+
+        logger.addAppender(asynAppender);
+
+        setProductName(productName);
+    }
+
+    protected ch.qos.logback.core.Appender getSizeRollingAppender(String productName, String file, String encoding,
+                                                                  String size, int maxBackupIndex) {
+        RollingFileAppender appender = new RollingFileAppender();
+        appender.setContext(LogbackLoggerContextUtil.getLoggerContext());
+
+        appender.setName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender");
+        appender.setAppend(true);
+        appender.setFile(LoggerHelper.getLogFile(productName, file));
+
+        SizeBasedTriggeringPolicy triggerPolicy = new SizeBasedTriggeringPolicy();
+        setMaxFileSize(triggerPolicy, size);
+        triggerPolicy.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        triggerPolicy.start();
+
+        FixedWindowRollingPolicy rolling = new FixedWindowRollingPolicy();
+        rolling.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        rolling.setParent(appender);
+        rolling.setFileNamePattern(LoggerHelper.getLogFile(productName, file) + ".%i");
+        rolling.setParent(appender);
+        if (maxBackupIndex >= 0) {
+            rolling.setMaxIndex(maxBackupIndex);
+        }
+        rolling.start();
+
+        appender.setRollingPolicy(rolling);
+        appender.setTriggeringPolicy(triggerPolicy);
+
+        PatternLayout layout = new PatternLayout();
+        layout.setPattern(LoggerHelper.getPattern(productName));
+        layout.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        layout.start();
+        appender.setLayout(layout);
+
+        // 启动
+        appender.start();
+        return appender;
+    }
+
+    /**
+     * logback 1.1.8开始不再支持setMaxFileSize(String)方法
+     */
+    protected void setMaxFileSize(Object policy, String size) {
+        try {
+            try {
+                Method setMaxFileSizeMethod = policy.getClass().getDeclaredMethod("setMaxFileSize", String.class);
+                setMaxFileSizeMethod.invoke(policy, size);
+            } catch (NoSuchMethodException e) {
+                Method setMaxFileSizeMethod = policy.getClass().getDeclaredMethod("setMaxFileSize", FileSize.class);
+                setMaxFileSizeMethod.invoke(policy, FileSize.valueOf(size));
+            }
+        } catch (Throwable t) {
+            throw new RuntimeException("Failed to setMaxFileSize", t);
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/option/LogbackActivateOption.java

@@ -0,0 +1,154 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.option;
+
+import java.io.File;
+import java.nio.charset.Charset;
+
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+
+import ch.qos.logback.classic.encoder.PatternLayoutEncoder;
+import ch.qos.logback.core.rolling.FixedWindowRollingPolicy;
+import ch.qos.logback.core.rolling.RollingFileAppender;
+import ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP;
+import ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy;
+import ch.qos.logback.core.rolling.TimeBasedRollingPolicy;
+
+/**
+ * ActivateOption的Logback 0.9.19及后续版本的实现
+ * 
+ * @author zhuyong 2014年3月20日 上午10:24:58
+ */
+@SuppressWarnings({ "rawtypes", "unchecked" })
+public class LogbackActivateOption extends Logback918ActivateOption {
+
+    public LogbackActivateOption(Object logger) {
+        super(logger);
+    }
+
+    protected ch.qos.logback.core.Appender getLogbackDailyRollingFileAppender(String productName, String file,
+                                                                              String encoding) {
+        RollingFileAppender appender = new RollingFileAppender();
+        appender.setContext(LogbackLoggerContextUtil.getLoggerContext());
+
+        appender.setName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender");
+        appender.setAppend(true);
+        appender.setFile(LoggerHelper.getLogFile(productName, file));
+
+        TimeBasedRollingPolicy rolling = new TimeBasedRollingPolicy();
+        rolling.setParent(appender);
+        rolling.setFileNamePattern(LoggerHelper.getLogFile(productName, file) + ".%d{yyyy-MM-dd}");
+        rolling.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        rolling.start();
+        appender.setRollingPolicy(rolling);
+
+        PatternLayoutEncoder layout = new PatternLayoutEncoder();
+        layout.setPattern(LoggerHelper.getPattern(productName));
+        layout.setCharset(Charset.forName(encoding));
+        appender.setEncoder(layout);
+        layout.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        layout.start();
+        // 启动
+        appender.start();
+
+        return appender;
+    }
+
+    protected ch.qos.logback.core.Appender getLogbackDailyAndSizeRollingFileAppender(String productName, String file,
+                                                                                     String encoding, String size) {
+        return getLogbackDailyAndSizeRollingFileAppender(productName, file, encoding, size, "yyyy-MM-dd", -1);
+    }
+
+    protected ch.qos.logback.core.Appender getLogbackDailyAndSizeRollingFileAppender(String productName, String file,
+                                                                                     String encoding, String size,
+                                                                                     String datePattern,
+                                                                                     int maxBackupIndex) {
+        RollingFileAppender appender = new RollingFileAppender();
+        appender.setContext(LogbackLoggerContextUtil.getLoggerContext());
+
+        appender.setName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender");
+        appender.setAppend(true);
+        appender.setFile(LoggerHelper.getLogFile(productName, file));
+
+        TimeBasedRollingPolicy rolling = new TimeBasedRollingPolicy();
+        rolling.setParent(appender);
+        if (maxBackupIndex >= 0) {
+            rolling.setMaxHistory(maxBackupIndex);
+        }
+        rolling.setFileNamePattern(LoggerHelper.getLogFile(productName, file) + ".%d{" + datePattern + "}.%i");
+        rolling.setContext(LogbackLoggerContextUtil.getLoggerContext());
+
+        SizeAndTimeBasedFNATP fnatp = new SizeAndTimeBasedFNATP();
+        setMaxFileSize(fnatp, size);
+        fnatp.setTimeBasedRollingPolicy(rolling);
+        rolling.setTimeBasedFileNamingAndTriggeringPolicy(fnatp);
+
+        rolling.start();
+        appender.setRollingPolicy(rolling);
+
+        PatternLayoutEncoder layout = new PatternLayoutEncoder();
+        layout.setPattern(LoggerHelper.getPattern(productName));
+        layout.setCharset(Charset.forName(encoding));
+        appender.setEncoder(layout);
+        layout.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        layout.start();
+
+        // 启动
+        appender.start();
+
+        return appender;
+    }
+
+    protected ch.qos.logback.core.Appender getSizeRollingAppender(String productName, String file, String encoding,
+                                                                  String size, int maxBackupIndex) {
+        RollingFileAppender appender = new RollingFileAppender();
+        appender.setContext(LogbackLoggerContextUtil.getLoggerContext());
+
+        appender.setName(productName + "." + file.replace(File.separatorChar, '.') + ".Appender");
+        appender.setAppend(true);
+        appender.setFile(LoggerHelper.getLogFile(productName, file));
+
+        SizeBasedTriggeringPolicy triggerPolicy = new SizeBasedTriggeringPolicy();
+        setMaxFileSize(triggerPolicy, size);
+        triggerPolicy.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        triggerPolicy.start();
+
+        FixedWindowRollingPolicy rolling = new FixedWindowRollingPolicy();
+        rolling.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        rolling.setParent(appender);
+        rolling.setFileNamePattern(LoggerHelper.getLogFile(productName, file) + ".%i");
+        rolling.setParent(appender);
+        if (maxBackupIndex >= 0) {
+            rolling.setMaxIndex(maxBackupIndex);
+        }
+        rolling.start();
+
+        appender.setRollingPolicy(rolling);
+        appender.setTriggeringPolicy(triggerPolicy);
+
+        PatternLayoutEncoder layout = new PatternLayoutEncoder();
+        layout.setPattern(LoggerHelper.getPattern(productName));
+        layout.setCharset(Charset.forName(encoding));
+        appender.setEncoder(layout);
+        layout.setContext(LogbackLoggerContextUtil.getLoggerContext());
+        layout.start();
+
+        // 启动
+        appender.start();
+
+        return appender;
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/option/LogbackLoggerContextUtil.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.option;
+
+import org.slf4j.ILoggerFactory;
+import org.slf4j.LoggerFactory;
+
+import ch.qos.logback.classic.LoggerContext;
+import ch.qos.logback.core.LogbackException;
+/**
+ * Logback Context Util
+ * @author Nacos
+ *
+ */
+public class LogbackLoggerContextUtil {
+
+    private static LoggerContext loggerContext = null;
+
+    public static LoggerContext getLoggerContext() {
+        if (loggerContext == null) {
+            ILoggerFactory lcObject = LoggerFactory.getILoggerFactory();
+
+            if (!(lcObject instanceof LoggerContext)) {
+                throw new LogbackException(
+                                           "Expected LOGBACK binding with SLF4J, but another log system has taken the place: "
+                                                   + lcObject.getClass().getSimpleName());
+            }
+
+            loggerContext = (LoggerContext) lcObject;
+        }
+
+        return loggerContext;
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/option/Slf4jLog4j2AdapterActivateOption.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.option;
+
+import java.lang.reflect.Field;
+
+import com.alibaba.nacos.client.logger.Logger;
+
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
+/**
+ * @author zhuyong on 2017/4/18.
+ */
+public class Slf4jLog4j2AdapterActivateOption extends Log4j2ActivateOption {
+
+    private static Field loggerField = null;
+
+    static {
+        try {
+            loggerField = org.apache.logging.slf4j.Log4jLogger.class.getDeclaredField("logger");
+            loggerField.setAccessible(true);
+        } catch (Exception e) {
+            throw new RuntimeException("logger must be instanceof org.apache.logging.slf4j.Log4jLogger", e);
+        }
+    }
+
+    public Slf4jLog4j2AdapterActivateOption(Object logger) {
+        super(null);
+
+        try {
+            org.apache.logging.log4j.core.Logger log4j2Logger = (org.apache.logging.log4j.core.Logger) loggerField.get(logger);
+            super.logger = log4j2Logger;
+            super.configuration = super.logger.getContext().getConfiguration();
+        } catch (Exception e) {
+            throw new RuntimeException("logger must be instanceof org.apache.logging.slf4j.Log4jLogger", e);
+        }
+    }
+
+    @Override
+    @SuppressFBWarnings("NM_WRONG_PACKAGE")
+    public void activateAppender(Logger logger) {
+        if (!(logger.getDelegate() instanceof org.apache.logging.slf4j.Log4jLogger)) {
+            throw new IllegalArgumentException(
+                    "logger must be org.apache.logging.slf4j.Log4jLogger, but it's "
+                            + logger.getDelegate().getClass());
+        }
+
+        try {
+            org.apache.logging.log4j.core.Logger log4j2Logger = (org.apache.logging.log4j.core.Logger) loggerField.get(logger.getDelegate());
+            super.activateAppender(log4j2Logger);
+        } catch (Exception e) {
+            throw new RuntimeException("activateAppender error, ", e);
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/option/Slf4jLog4jAdapterActivateOption.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.option;
+
+import java.lang.reflect.Field;
+
+import com.alibaba.nacos.client.logger.Logger;
+
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
+/**
+ * Slf4j-log4j12架构下的ActivateOption实现
+ *
+ * @author zhuyong 2014年3月20日 上午10:26:04
+ */
+public class Slf4jLog4jAdapterActivateOption extends Log4jActivateOption {
+
+    private static Field loggerField = null;
+
+    static {
+        try {
+            loggerField = org.slf4j.impl.Log4jLoggerAdapter.class.getDeclaredField("logger");
+            loggerField.setAccessible(true);
+        } catch (Exception e) {
+            throw new RuntimeException("logger must be instanceof org.slf4j.impl.Log4jLoggerAdapter", e);
+        }
+    }
+
+    public Slf4jLog4jAdapterActivateOption(Object logger) {
+        super(null);
+
+        try {
+            org.apache.log4j.Logger log4jLogger = (org.apache.log4j.Logger) loggerField.get(logger);
+            super.logger = log4jLogger;
+        } catch (Exception e) {
+            throw new RuntimeException("logger must be instanceof org.slf4j.impl.Log4jLoggerAdapter", e);
+        }
+    }
+
+    @Override
+    @SuppressFBWarnings("NM_WRONG_PACKAGE")
+    public void activateAppender(Logger logger) {
+        if (!(logger.getDelegate() instanceof org.slf4j.impl.Log4jLoggerAdapter)) {
+            throw new IllegalArgumentException(
+                    "logger must be org.slf4j.impl.Log4jLoggerAdapter, but it's "
+                            + logger.getDelegate().getClass());
+        }
+
+        try {
+            org.apache.log4j.Logger log4jLogger =
+                    (org.apache.log4j.Logger) loggerField.get(logger.getDelegate());
+            super.activateAppender(log4jLogger);
+            setProductName(logger.getProductName());
+        } catch (Exception e) {
+            throw new RuntimeException("activateAppender error, ", e);
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/slf4j/Slf4jLogger.java

@@ -0,0 +1,178 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.slf4j;
+
+import java.lang.reflect.Constructor;
+
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.option.ActivateOption;
+import com.alibaba.nacos.client.logger.support.LoggerHelper;
+import com.alibaba.nacos.client.logger.support.LoggerSupport;
+import com.alibaba.nacos.client.logger.util.MessageUtil;
+/**
+ * slf4j logger
+ * @author Nacos
+ *
+ */
+public class Slf4jLogger extends LoggerSupport implements Logger {
+
+    private static boolean   CanUseEncoder = false;
+    private static final String LOGBACK_CLASSNAME = "ch.qos.logback.classic.Logger";
+    private static final String SLF4J_CLASSNAME = "org.slf4j.impl.Log4jLoggerAdapter";
+    private static final String SLF4JLOG4J_CLASSNAME = "org.apache.logging.slf4j.Log4jLogger";
+    static {
+        try {
+            // logback从0.9.19开始采用encoder，@see http://logback.qos.ch/manual/encoders.html
+            Class.forName("ch.qos.logback.classic.encoder.PatternLayoutEncoder");
+            CanUseEncoder = true;
+        } catch (ClassNotFoundException e) {
+            CanUseEncoder = false;
+        }
+    }
+
+    private org.slf4j.Logger delegate;
+
+    @SuppressWarnings("unchecked")
+    public
+    Slf4jLogger(org.slf4j.Logger delegate){
+        super(delegate);
+        if (delegate == null) {
+            throw new IllegalArgumentException("delegate Logger is null");
+        }
+        this.delegate = delegate;
+
+        String activateOptionClass = null;
+        if (LOGBACK_CLASSNAME.equals(delegate.getClass().getName())) {
+            if (CanUseEncoder) {
+                activateOptionClass = "com.alibaba.nacos.client.logger.option.LogbackActivateOption";
+            } else {
+                activateOptionClass = "com.alibaba.nacos.client.logger.option.Logback918ActivateOption";
+            }
+        } else if (SLF4J_CLASSNAME.equals(delegate.getClass().getName())) {
+            activateOptionClass = "com.alibaba.nacos.client.logger.option.Slf4jLog4jAdapterActivateOption";
+        } else if (SLF4JLOG4J_CLASSNAME.equals(delegate.getClass().getName())) {
+            activateOptionClass = "com.alibaba.nacos.client.logger.option.Slf4jLog4j2AdapterActivateOption";
+        }
+
+        try {
+            Class<ActivateOption> clazz = (Class<ActivateOption>) Class.forName(activateOptionClass);
+            Constructor<ActivateOption> c = clazz.getConstructor(Object.class);
+            this.activateOption = c.newInstance(delegate);
+        } catch (Exception e) {
+            throw new IllegalArgumentException("delegate must be logback impl or slf4j-log4j impl", e);
+        }
+    }
+
+    @Override
+    public void debug(String context, String message) {
+        if (isDebugEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.debug(MessageUtil.getMessage(context, message));
+        }
+    }
+
+    @Override
+    public void debug(String context, String format, Object... args) {
+        if (isDebugEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.debug(MessageUtil.getMessage(context, format), args);
+        }
+    }
+
+    @Override
+    public void info(String context, String message) {
+        if (isInfoEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.info(MessageUtil.getMessage(context, message));
+        }
+    }
+
+    @Override
+    public void info(String context, String format, Object... args) {
+        if (isInfoEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.info(MessageUtil.getMessage(context, format), args);
+        }
+    }
+
+    @Override
+    public void warn(String message, Throwable t) {
+        if (isWarnEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.warn(MessageUtil.getMessage(null, message), t);
+        }
+    }
+
+    @Override
+    public void warn(String context, String message) {
+        if (isWarnEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.warn(MessageUtil.getMessage(context, message));
+        }
+    }
+
+    @Override
+    public void warn(String context, String format, Object... args) {
+        if (isWarnEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.warn(MessageUtil.getMessage(context, format), args);
+        }
+    }
+
+    @Override
+    public void error(String context, String errorCode, String message) {
+        if (isErrorEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.error(MessageUtil.getMessage(context, errorCode, message));
+        }
+    }
+
+    @Override
+    public void error(String context, String errorCode, String message, Throwable t) {
+        if (isErrorEnabled()) {
+            message = LoggerHelper.getResourceBundleString(getProductName(), message);
+            delegate.error(MessageUtil.getMessage(context, errorCode, message), t);
+        }
+    }
+
+    @Override
+    public void error(String context, String errorCode, String format, Object... args) {
+        if (isErrorEnabled()) {
+            format = LoggerHelper.getResourceBundleString(getProductName(), format);
+            delegate.error(MessageUtil.getMessage(context, errorCode, format), args);
+        }
+    }
+
+    @Override
+    public boolean isDebugEnabled() {
+        return delegate.isDebugEnabled();
+    }
+
+    @Override
+    public boolean isInfoEnabled() {
+        return delegate.isInfoEnabled();
+    }
+
+    @Override
+    public boolean isWarnEnabled() {
+        return delegate.isWarnEnabled();
+    }
+
+    @Override
+    public boolean isErrorEnabled() {
+        return delegate.isErrorEnabled();
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/slf4j/Slf4jLoggerFactory.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.slf4j;
+
+
+import com.alibaba.nacos.client.logger.Logger;
+import com.alibaba.nacos.client.logger.nop.NopLogger;
+import com.alibaba.nacos.client.logger.support.ILoggerFactory;
+import com.alibaba.nacos.client.logger.support.LogLog;
+/**
+ * Slf4jLogger Factory
+ * @author Nacos
+ *
+ */
+public class Slf4jLoggerFactory implements ILoggerFactory {
+
+    public Slf4jLoggerFactory() throws ClassNotFoundException {
+        Class.forName("org.slf4j.impl.StaticLoggerBinder");
+    }
+
+    public Logger getLogger(String name) {
+        try {
+            return new Slf4jLogger(org.slf4j.LoggerFactory.getLogger(name));
+        } catch (Throwable t) {
+            LogLog.error("Failed to get Slf4jLogger", t);
+            return new NopLogger();
+        }
+    }
+
+    public Logger getLogger(Class<?> clazz) {
+        try {
+            return new Slf4jLogger(org.slf4j.LoggerFactory.getLogger(clazz));
+        } catch (Throwable t) {
+            LogLog.error("Failed to get Slf4jLogger", t);
+            return new NopLogger();
+        }
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/support/AppenderInfo.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.nacos.client.logger.support;
+
+import java.util.HashMap;
+
+/**
+ * @author zhuyong on 2017/6/30.
+ */
+public class AppenderInfo extends HashMap {
+
+    private static String name = "name";
+    private static String type = "type";
+    private static String file = "file";
+
+    public String getName() {
+        return (String) get(AppenderInfo.name);
+    }
+
+    public void setName(String name) {
+        put(AppenderInfo.name, name);
+    }
+
+    public void setType(String type) {
+        put(AppenderInfo.type, type);
+    }
+
+    public void setFile(String file) {
+        put(AppenderInfo.file, file);
+    }
+
+    public void withDetail(String name, Object value) {
+        put(name, value);
+    }
+}

client/src/main/java/com/alibaba/nacos/client/logger/support/DepthThrowableRenderer.java

@@ -0,0 +1,90 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * Copyright 2014 Alibaba.com All right reserved. This software is the
+ * confidential and proprietary information of Alibaba.com ("Confidential
+ * Information"). You shall not disclose such Confidential Information and shall
+ * use it only in accordance with the terms of the license agreement you entered
+ * into with Alibaba.com.
+ */
+package com.alibaba.nacos.client.logger.support;
+
+import java.io.IOException;
+import java.io.InterruptedIOException;
+import java.io.LineNumberReader;
+import java.io.PrintWriter;
+import java.io.StringReader;
+import java.io.StringWriter;
+import java.util.ArrayList;
+
+import org.apache.log4j.spi.ThrowableRenderer;
+
+/**
+ * 针对 Log4j 1.2.16 及以上版本，提供对异常栈的深度控制
+ *
+ * @author zhuyong 2014年9月19日 上午10:31:48
+ */
+public final class DepthThrowableRenderer implements ThrowableRenderer {
+
+    private int depth = -1;
+
+    public DepthThrowableRenderer(int depth) {
+        this.depth = depth;
+    }
+
+    public void setDepth(int depth) {
+        this.depth = depth;
+    }
+
+    public String[] doRender(final Throwable throwable) {
+        return render(throwable, depth);
+    }
+
+    /**
+     * Render throwable using Throwable.printStackTrace.
+     *
+     * @param throwable throwable, may not be null.
+     * @param depth     stack depth
+     * @return string representation.
+     */
+    public static String[] render(final Throwable throwable, final int depth) {
+        StringWriter sw = new StringWriter();
+        PrintWriter pw = new PrintWriter(sw);
+        try {
+            throwable.printStackTrace(pw);
+        } catch (RuntimeException ex) {
+        }
+        pw.flush();
+        LineNumberReader reader = new LineNumberReader(new StringReader(sw.toString()));
+        ArrayList<String> lines = new ArrayList<String>();
+        try {
+            String line = reader.readLine();
+            int count = 0;
+            while (line != null && (depth == -1 || count++ <= depth)) {
+                lines.add(line);
+                line = reader.readLine();
+            }
+        } catch (IOException ex) {
+            if (ex instanceof InterruptedIOException) {
+                Thread.currentThread().interrupt();
+            }
+            lines.add(ex.toString());
+        }
+        String[] tempRep = new String[lines.size()];
+        lines.toArray(tempRep);
+        return tempRep;
+    }
+}