Add support for `spring-devtools.properties`

Allow `META-INF/spring-devtools.properties` files to be used by
application developers to declare is specific jars should be included
or excluded from the RestartClassLoader.

A typical example where this might be used is a company that develops
it's own set of internal JARs that are used by developers but not
usually imported into their IDE.

See gh-3316

spring-boot-devtools/src/main/java/org/springframework/boot/devtools/restart/ChangeableUrls.java

@@ -23,7 +23,8 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
-import java.util.regex.Pattern;
+
+import org.springframework.boot.devtools.settings.DevToolsSettings;
 
 /**
  * A filtered collections of URLs which can be change after the application has started.
@@ -32,48 +33,24 @@ import java.util.regex.Pattern;
  */
 final class ChangeableUrls implements Iterable<URL> {
 
-	private static final String[] SKIPPED_PROJECTS = { "spring-boot",
-			"spring-boot-devtools", "spring-boot-autoconfigure", "spring-boot-actuator",
-			"spring-boot-starter" };
-
-	private static final Pattern STARTER_PATTERN = Pattern
-			.compile("\\/spring-boot-starter-[\\w-]+\\/");
-
 	private final List<URL> urls;
 
 	private ChangeableUrls(URL... urls) {
+		DevToolsSettings settings = DevToolsSettings.get();
 		List<URL> reloadableUrls = new ArrayList<URL>(urls.length);
 		for (URL url : urls) {
-			if (isReloadable(url)) {
+			if ((settings.isRestartInclude(url) || isFolderUrl(url.toString()))
+					&& !settings.isRestartExclude(url)) {
 				reloadableUrls.add(url);
 			}
 		}
 		this.urls = Collections.unmodifiableList(reloadableUrls);
 	}
 
-	private boolean isReloadable(URL url) {
-		String urlString = url.toString();
-		return isFolderUrl(urlString) && !isSkipped(urlString);
-	}
-
 	private boolean isFolderUrl(String urlString) {
 		return urlString.startsWith("file:") && urlString.endsWith("/");
 	}
 
-	private boolean isSkipped(String urlString) {
-		// Skip certain spring-boot projects to allow them to be imported in the same IDE
-		for (String skipped : SKIPPED_PROJECTS) {
-			if (urlString.contains("/" + skipped + "/target/classes/")) {
-				return true;
-			}
-		}
-		// Skip all starter projects
-		if (STARTER_PATTERN.matcher(urlString).find()) {
-			return true;
-		}
-		return false;
-	}
-
 	@Override
 	public Iterator<URL> iterator() {
 		return this.urls.iterator();

spring-boot-devtools/src/main/java/org/springframework/boot/devtools/settings/DevToolsSettings.java

@@ -0,0 +1,116 @@
+/*
+ * 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.devtools.settings;
+
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.regex.Pattern;
+
+import org.springframework.core.io.UrlResource;
+import org.springframework.core.io.support.PropertiesLoaderUtils;
+
+/**
+ * DevTools settings loaded from {@literal /META-INF/spring-devtools.properties} files.
+ *
+ * @author Phillip Webb
+ * @since 1.3.0
+ */
+public class DevToolsSettings {
+
+	/**
+	 * The location to look for settings properties. Can be present in multiple JAR files.
+	 */
+	public static final String SETTINGS_RESOURCE_LOCATION = "META-INF/spring-devtools.properties";
+
+	private static DevToolsSettings settings;
+
+	private final List<Pattern> restartIncludePatterns = new ArrayList<Pattern>();
+
+	private final List<Pattern> restartExcludePatterns = new ArrayList<Pattern>();
+
+	DevToolsSettings() {
+	}
+
+	void add(Map<?, ?> properties) {
+		Map<String, Pattern> includes = getPatterns(properties, "restart.include.");
+		this.restartIncludePatterns.addAll(includes.values());
+		Map<String, Pattern> excludes = getPatterns(properties, "restart.exclude.");
+		this.restartExcludePatterns.addAll(excludes.values());
+	}
+
+	private Map<String, Pattern> getPatterns(Map<?, ?> properties, String prefix) {
+		Map<String, Pattern> patterns = new LinkedHashMap<String, Pattern>();
+		for (Map.Entry<?, ?> entry : properties.entrySet()) {
+			String name = String.valueOf(entry.getKey());
+			if (name.startsWith(prefix)) {
+				Pattern pattern = Pattern.compile((String) entry.getValue());
+				patterns.put(name, pattern);
+			}
+		}
+		return patterns;
+	}
+
+	public boolean isRestartInclude(URL url) {
+		return isMatch(url.toString(), this.restartIncludePatterns);
+	}
+
+	public boolean isRestartExclude(URL url) {
+		return isMatch(url.toString(), this.restartExcludePatterns);
+	}
+
+	private boolean isMatch(String url, List<Pattern> patterns) {
+		for (Pattern pattern : patterns) {
+			if (pattern.matcher(url).find()) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	public static DevToolsSettings get() {
+		if (settings == null) {
+			settings = load();
+		}
+		return settings;
+	}
+
+	static DevToolsSettings load() {
+		return load(SETTINGS_RESOURCE_LOCATION);
+	}
+
+	static DevToolsSettings load(String location) {
+		try {
+			DevToolsSettings settings = new DevToolsSettings();
+			Enumeration<URL> urls = Thread.currentThread().getContextClassLoader()
+					.getResources(location);
+			while (urls.hasMoreElements()) {
+				settings.add(PropertiesLoaderUtils
+						.loadProperties(new UrlResource(urls.nextElement())));
+			}
+			return settings;
+		}
+		catch (Exception ex) {
+			throw new IllegalStateException("Unable to load devtools settings from "
+					+ "location [" + location + "]", ex);
+		}
+	}
+
+}

spring-boot-devtools/src/main/resources/META-INF/spring-devtools.properties

@@ -0,0 +1,6 @@
+restart.exclude.spring-boot=/spring-boot/target/classes/
+restart.exclude.spring-boot-devtools=/spring-boot-devtools/target/classes/
+restart.exclude.spring-boot-autoconfigure=/spring-boot-autoconfigure/target/classes/
+restart.exclude.spring-boot-actuator=/spring-boot-actuator/target/classes/
+restart.exclude.spring-boot-starter=/spring-boot-starter/target/classes/
+restart.exclude.spring-boot-starters=/spring-boot-starter-[\\w-]+/

spring-boot-devtools/src/test/java/org/springframework/boot/devtools/settings/DevToolsSettingsTests.java

@@ -0,0 +1,81 @@
+/*
+ * 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.devtools.settings;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.URL;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+import static org.hamcrest.Matchers.equalTo;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * Tests for {@link DevToolsSettings}.
+ *
+ * @author Phillip Webb
+ */
+public class DevToolsSettingsTests {
+
+	@Rule
+	public TemporaryFolder temporaryFolder = new TemporaryFolder();
+
+	private static final String ROOT = DevToolsSettingsTests.class.getPackage().getName()
+			.replace(".", "/") + "/";
+
+	@Test
+	public void includePatterns() throws Exception {
+		DevToolsSettings settings = DevToolsSettings
+				.load(ROOT + "spring-devtools-include.properties");
+		assertThat(settings.isRestartInclude(new URL("file://test/a")), equalTo(true));
+		assertThat(settings.isRestartInclude(new URL("file://test/b")), equalTo(true));
+		assertThat(settings.isRestartInclude(new URL("file://test/c")), equalTo(false));
+	}
+
+	@Test
+	public void excludePatterns() throws Exception {
+		DevToolsSettings settings = DevToolsSettings
+				.load(ROOT + "spring-devtools-exclude.properties");
+		assertThat(settings.isRestartExclude(new URL("file://test/a")), equalTo(true));
+		assertThat(settings.isRestartExclude(new URL("file://test/b")), equalTo(true));
+		assertThat(settings.isRestartExclude(new URL("file://test/c")), equalTo(false));
+	}
+
+	@Test
+	public void defaultIncludePatterns() throws Exception {
+		DevToolsSettings settings = DevToolsSettings.get();
+		assertTrue(settings.isRestartExclude(makeUrl("spring-boot")));
+		assertTrue(settings.isRestartExclude(makeUrl("spring-boot-autoconfigure")));
+		assertTrue(settings.isRestartExclude(makeUrl("spring-boot-actuator")));
+		assertTrue(settings.isRestartExclude(makeUrl("spring-boot-starter")));
+		assertTrue(settings.isRestartExclude(makeUrl("spring-boot-starter-some-thing")));
+	}
+
+	private URL makeUrl(String name) throws IOException {
+		File file = this.temporaryFolder.newFolder();
+		file = new File(file, name);
+		file = new File(file, "target");
+		file = new File(file, "classes");
+		file.mkdirs();
+		return file.toURI().toURL();
+	}
+
+}

spring-boot-devtools/src/test/resources/org/springframework/boot/devtools/settings/spring-devtools-exclude.properties

@@ -0,0 +1,2 @@
+restart.exclude.a=a.*
+restart.exclude.b=b.*

spring-boot-devtools/src/test/resources/org/springframework/boot/devtools/settings/spring-devtools-include.properties

@@ -0,0 +1,2 @@
+restart.include.a=a.*
+restart.include.b=b.*