Log warning if scanning org or org.springframework

Update ConfigurationWarningsApplicationContextInitializer to also log
warnings if the user is scanning `org` or `org.springframework`.

Fixes gh-4777

spring-boot/src/main/java/org/springframework/boot/context/ConfigurationWarningsApplicationContextInitializer.java

@@ -16,6 +16,13 @@
 
 package org.springframework.boot.context;
 
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Set;
+
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
@@ -33,7 +40,6 @@ import org.springframework.core.PriorityOrdered;
 import org.springframework.core.annotation.AnnotationAttributes;
 import org.springframework.core.type.AnnotationMetadata;
 import org.springframework.util.ClassUtils;
-import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
 
 /**
@@ -60,7 +66,7 @@ public class ConfigurationWarningsApplicationContextInitializer
 	 * @return the checks to apply
 	 */
 	protected Check[] getChecks() {
-		return new Check[] { new ComponentScanDefaultPackageCheck() };
+		return new Check[] { new ComponentScanPackageCheck() };
 	}
 
 	/**
@@ -120,62 +126,101 @@ public class ConfigurationWarningsApplicationContextInitializer
 	}
 
 	/**
-	 * {@link Check} for {@code @ComponentScan} on the default package.
+	 * {@link Check} for {@code @ComponentScan} on problematic package.
 	 */
-	protected static class ComponentScanDefaultPackageCheck implements Check {
+	protected static class ComponentScanPackageCheck implements Check {
+
+		private static final Set<String> PROBLEM_PACKAGES;
+
+		static {
+			Set<String> pacakges = new HashSet<String>();
+			pacakges.add("org.springframework");
+			pacakges.add("org");
+			PROBLEM_PACKAGES = Collections.unmodifiableSet(pacakges);
+		}
 
 		@Override
 		public String getWarning(BeanDefinitionRegistry registry) {
-			if (isComponentScanningDefaultPackage(registry)) {
-				return "Your ApplicationContext is unlikely to start due to a "
-						+ "@ComponentScan of the default package.";
+			Set<String> scannedPackages = getComponentScanningPackages(registry);
+			List<String> problematicPackages = getProblematicPackages(scannedPackages);
+			if (problematicPackages.isEmpty()) {
+				return null;
 			}
-			return null;
+			return "Your ApplicationContext is unlikely to "
+					+ "start due to a @ComponentScan of "
+					+ StringUtils.collectionToDelimitedString(problematicPackages, ", ")
+					+ ".";
 		}
 
-		private boolean isComponentScanningDefaultPackage(
+		protected Set<String> getComponentScanningPackages(
 				BeanDefinitionRegistry registry) {
+			Set<String> packages = new LinkedHashSet<String>();
 			String[] names = registry.getBeanDefinitionNames();
 			for (String name : names) {
 				BeanDefinition definition = registry.getBeanDefinition(name);
 				if (definition instanceof AnnotatedBeanDefinition) {
 					AnnotatedBeanDefinition annotatedDefinition = (AnnotatedBeanDefinition) definition;
-					if (isScanningDefaultPackage(annotatedDefinition.getMetadata())) {
-						return true;
-					}
+					addComponentScanningPackages(packages,
+							annotatedDefinition.getMetadata());
 				}
 			}
-			return false;
+			return packages;
 		}
 
-		private boolean isScanningDefaultPackage(AnnotationMetadata metadata) {
+		private void addComponentScanningPackages(Set<String> packages,
+				AnnotationMetadata metadata) {
 			AnnotationAttributes attributes = AnnotationAttributes.fromMap(metadata
 					.getAnnotationAttributes(ComponentScan.class.getName(), true));
-			if (attributes != null && hasNoScanPackageSpecified(attributes)) {
-				if (isInDefaultPackage(metadata.getClassName())) {
-					return true;
+			if (attributes != null) {
+				addPackages(packages, attributes.getStringArray("value"));
+				addPackages(packages, attributes.getStringArray("basePackages"));
+				addClasses(packages, attributes.getStringArray("basePackageClasses"));
+				if (packages.isEmpty()) {
+					packages.add(ClassUtils.getPackageName(metadata.getClassName()));
 				}
 			}
-			return false;
 		}
 
-		private boolean hasNoScanPackageSpecified(AnnotationAttributes attributes) {
-			return isAllEmpty(attributes, "value", "basePackages", "basePackageClasses");
-		}
-
-		private boolean isAllEmpty(AnnotationAttributes attributes, String... names) {
-			for (String name : names) {
-				if (!ObjectUtils.isEmpty(attributes.getStringArray(name))) {
-					return false;
+		private void addPackages(Set<String> packages, String[] values) {
+			if (values != null) {
+				for (String value : values) {
+					packages.add(value);
 				}
 			}
-			return true;
 		}
 
-		protected boolean isInDefaultPackage(String className) {
-			String packageName = ClassUtils.getPackageName(className);
-			return StringUtils.isEmpty(packageName);
+		private void addClasses(Set<String> packages, String[] values) {
+			if (values != null) {
+				for (String value : values) {
+					packages.add(ClassUtils.getPackageName(value));
+				}
+			}
 		}
+
+		private List<String> getProblematicPackages(Set<String> scannedPackages) {
+			List<String> problematicPackages = new ArrayList<String>();
+			for (String scannedPackage : scannedPackages) {
+				if (isProblematicPackage(scannedPackage)) {
+					problematicPackages.add(getDisplayName(scannedPackage));
+				}
+			}
+			return problematicPackages;
+		}
+
+		private boolean isProblematicPackage(String scannedPackage) {
+			if (scannedPackage == null || scannedPackage.length() == 0) {
+				return true;
+			}
+			return PROBLEM_PACKAGES.contains(scannedPackage);
+		}
+
+		private String getDisplayName(String scannedPackage) {
+			if (scannedPackage == null || scannedPackage.length() == 0) {
+				return "the default package";
+			}
+			return "'" + scannedPackage + "'";
+		}
+
 	}
 
 }

spring-boot/src/test/java/org/springframework/boot/context/ConfigurationWarningsApplicationContextInitializerTests.java

@@ -16,17 +16,23 @@
 
 package org.springframework.boot.context;
 
+import java.util.LinkedHashSet;
+import java.util.Set;
+
 import org.junit.Rule;
 import org.junit.Test;
 
-import org.springframework.boot.context.ConfigurationWarningsApplicationContextInitializer.ComponentScanDefaultPackageCheck;
-import org.springframework.boot.context.configwarnings.InDefaultPackageConfiguration;
-import org.springframework.boot.context.configwarnings.InDefaultPackageWithBasePackageClassesConfiguration;
-import org.springframework.boot.context.configwarnings.InDefaultPackageWithBasePackagesConfiguration;
-import org.springframework.boot.context.configwarnings.InDefaultPackageWithMetaAnnotationConfiguration;
-import org.springframework.boot.context.configwarnings.InDefaultPackageWithValueConfiguration;
-import org.springframework.boot.context.configwarnings.InDefaultPackageWithoutScanConfiguration;
-import org.springframework.boot.context.configwarnings.InRealPackageConfiguration;
+import org.springframework.beans.factory.support.BeanDefinitionRegistry;
+import org.springframework.boot.context.ConfigurationWarningsApplicationContextInitializer.ComponentScanPackageCheck;
+import org.springframework.boot.context.configwarnings.dflt.InDefaultPackageConfiguration;
+import org.springframework.boot.context.configwarnings.dflt.InDefaultPackageWithBasePackageClassesConfiguration;
+import org.springframework.boot.context.configwarnings.dflt.InDefaultPackageWithBasePackagesConfiguration;
+import org.springframework.boot.context.configwarnings.dflt.InDefaultPackageWithMetaAnnotationConfiguration;
+import org.springframework.boot.context.configwarnings.dflt.InDefaultPackageWithValueConfiguration;
+import org.springframework.boot.context.configwarnings.dflt.InDefaultPackageWithoutScanConfiguration;
+import org.springframework.boot.context.configwarnings.orgspring.InOrgSpringPackageConfiguration;
+import org.springframework.boot.context.configwarnings.real.InRealButScanningProblemPackages;
+import org.springframework.boot.context.configwarnings.real.InRealPackageConfiguration;
 import org.springframework.boot.test.OutputCapture;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 
@@ -41,8 +47,11 @@ import static org.junit.Assert.assertThat;
  */
 public class ConfigurationWarningsApplicationContextInitializerTests {
 
-	private static final String SCAN_WARNING = "Your ApplicationContext is unlikely to "
-			+ "start due to a @ComponentScan of the default package";
+	private static final String DEFAULT_SCAN_WARNING = "Your ApplicationContext is unlikely to "
+			+ "start due to a @ComponentScan of the default package.";
+
+	private static final String ORGSPRING_SCAN_WARNING = "Your ApplicationContext is unlikely to "
+			+ "start due to a @ComponentScan of 'org.springframework'.";
 
 	@Rule
 	public OutputCapture output = new OutputCapture();
@@ -50,43 +59,58 @@ public class ConfigurationWarningsApplicationContextInitializerTests {
 	@Test
 	public void logWarningInDefaultPackage() {
 		load(InDefaultPackageConfiguration.class);
-		assertThat(this.output.toString(), containsString(SCAN_WARNING));
+		assertThat(this.output.toString(), containsString(DEFAULT_SCAN_WARNING));
 	}
 
 	@Test
 	public void logWarningInDefaultPackageAndMetaAnnotation() {
 		load(InDefaultPackageWithMetaAnnotationConfiguration.class);
-		assertThat(this.output.toString(), containsString(SCAN_WARNING));
+		assertThat(this.output.toString(), containsString(DEFAULT_SCAN_WARNING));
 	}
 
 	@Test
 	public void noLogIfInRealPackage() throws Exception {
 		load(InRealPackageConfiguration.class);
-		assertThat(this.output.toString(), not(containsString(SCAN_WARNING)));
+		assertThat(this.output.toString(), not(containsString(DEFAULT_SCAN_WARNING)));
 	}
 
 	@Test
 	public void noLogWithoutComponentScanAnnotation() throws Exception {
 		load(InDefaultPackageWithoutScanConfiguration.class);
-		assertThat(this.output.toString(), not(containsString(SCAN_WARNING)));
+		assertThat(this.output.toString(), not(containsString(DEFAULT_SCAN_WARNING)));
 	}
 
 	@Test
 	public void noLogIfHasValue() throws Exception {
 		load(InDefaultPackageWithValueConfiguration.class);
-		assertThat(this.output.toString(), not(containsString(SCAN_WARNING)));
+		assertThat(this.output.toString(), not(containsString(DEFAULT_SCAN_WARNING)));
 	}
 
 	@Test
 	public void noLogIfHasBasePackages() throws Exception {
 		load(InDefaultPackageWithBasePackagesConfiguration.class);
-		assertThat(this.output.toString(), not(containsString(SCAN_WARNING)));
+		assertThat(this.output.toString(), not(containsString(DEFAULT_SCAN_WARNING)));
 	}
 
 	@Test
 	public void noLogIfHasBasePackageClasses() throws Exception {
 		load(InDefaultPackageWithBasePackageClassesConfiguration.class);
-		assertThat(this.output.toString(), not(containsString(SCAN_WARNING)));
+		assertThat(this.output.toString(), not(containsString(DEFAULT_SCAN_WARNING)));
+	}
+
+	@Test
+	public void logWarningInOrgSpringPackage() {
+		load(InOrgSpringPackageConfiguration.class);
+		assertThat(this.output.toString(), containsString(ORGSPRING_SCAN_WARNING));
+	}
+
+	@Test
+	public void logWarningIfScanningProblemPackages() throws Exception {
+		load(InRealButScanningProblemPackages.class);
+		assertThat(this.output.toString(),
+				containsString("Your ApplicationContext is unlikely to start due to a "
+						+ "@ComponentScan of the default package, 'org.springframework'."));
+
 	}
 
 	private void load(Class<?> configClass) {
@@ -121,12 +145,25 @@ public class ConfigurationWarningsApplicationContextInitializerTests {
 	 * Testable ComponentScanDefaultPackageCheck that doesn't need to use the default
 	 * package.
 	 */
-	static class TestComponentScanDefaultPackageCheck
-			extends ComponentScanDefaultPackageCheck {
+	static class TestComponentScanDefaultPackageCheck extends ComponentScanPackageCheck {
 
 		@Override
-		protected boolean isInDefaultPackage(String className) {
-			return className.contains("InDefault");
+		protected Set<String> getComponentScanningPackages(
+				BeanDefinitionRegistry registry) {
+			Set<String> scannedPackages = super.getComponentScanningPackages(registry);
+			Set<String> result = new LinkedHashSet<String>();
+			for (String scannedPackage : scannedPackages) {
+				if (scannedPackage.endsWith("dflt")) {
+					result.add("");
+				}
+				if (scannedPackage.endsWith("orgspring")) {
+					result.add("org.springframework");
+				}
+				else {
+					result.add(scannedPackage);
+				}
+			}
+			return result;
 		}
 
 	}

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/annotation/MetaComponentScan.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.context.configwarnings;
+package org.springframework.boot.context.configwarnings.annotation;
 
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/dflt/InDefaultPackageConfiguration.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.context.configwarnings;
+package org.springframework.boot.context.configwarnings.dflt;
 
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/dflt/InDefaultPackageWithBasePackageClassesConfiguration.java

@@ -14,9 +14,9 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.context.configwarnings;
+package org.springframework.boot.context.configwarnings.dflt;
 
-import org.springframework.boot.context.configwarnings.nested.ExampleBean;
+import org.springframework.boot.context.configwarnings.real.nested.ExampleBean;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
 

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/dflt/InDefaultPackageWithBasePackagesConfiguration.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.context.configwarnings;
+package org.springframework.boot.context.configwarnings.dflt;
 
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/dflt/InDefaultPackageWithMetaAnnotationConfiguration.java

@@ -14,8 +14,9 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.context.configwarnings;
+package org.springframework.boot.context.configwarnings.dflt;
 
+import org.springframework.boot.context.configwarnings.annotation.MetaComponentScan;
 import org.springframework.context.annotation.Configuration;
 
 @Configuration

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/dflt/InDefaultPackageWithValueConfiguration.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.context.configwarnings;
+package org.springframework.boot.context.configwarnings.dflt;
 
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/dflt/InDefaultPackageWithoutScanConfiguration.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.context.configwarnings;
+package org.springframework.boot.context.configwarnings.dflt;
 
 import org.springframework.context.annotation.Configuration;
 

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/orgspring/InOrgSpringPackageConfiguration.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2012-2014 the original author or authors.
+ *
+ * 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 org.springframework.boot.context.configwarnings.orgspring;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@ComponentScan
+public class InOrgSpringPackageConfiguration {
+}

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/real/InRealButScanningProblemPackages.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2012-2015 the original author or authors.
+ *
+ * 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 org.springframework.boot.context.configwarnings.real;
+
+import org.springframework.boot.context.configwarnings.dflt.InDefaultPackageConfiguration;
+import org.springframework.boot.context.configwarnings.orgspring.InOrgSpringPackageConfiguration;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@ComponentScan(basePackageClasses = { InDefaultPackageConfiguration.class,
+		InOrgSpringPackageConfiguration.class })
+public class InRealButScanningProblemPackages {
+
+}

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/real/InRealPackageConfiguration.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.context.configwarnings;
+package org.springframework.boot.context.configwarnings.real;
 
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;

spring-boot/src/test/java/org/springframework/boot/context/configwarnings/real/nested/ExampleBean.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.context.configwarnings.nested;
+package org.springframework.boot.context.configwarnings.real.nested;
 
 import org.springframework.stereotype.Component;