Merge pull request #3 from gitblit/stop_plugin

Add support for starting, stopping, and unloading a plugin

4 files changed, 192 insertions, 60 deletions

diff --git a/pf4j/pom.xml b/pf4j/pom.xml
index 10c4b05..183c10e 100644
--- a/pf4j/pom.xml
+++ b/pf4j/pom.xml
@@ -32,6 +32,12 @@
             <artifactId>slf4j-api</artifactId>
             <version>1.6.4</version>
         </dependency>
+          <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>4.8.1</version>
+      <scope>test</scope>
+    </dependency>
     </dependencies>
 
 </project>
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginManager.java b/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginManager.java
index 013eadf..1bca676 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginManager.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginManager.java
@@ -1,11 +1,11 @@
 /*

  * Copyright 2012 Decebal Suiu

- * 

+ *

  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with

  * the License. You may obtain a copy of the License in the LICENSE file, or 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.

@@ -19,6 +19,7 @@ import java.util.ArrayList;
 import java.util.Arrays;

 import java.util.Collections;

 import java.util.HashMap;

+import java.util.Iterator;

 import java.util.List;

 import java.util.Map;

 

@@ -42,7 +43,7 @@ import ro.fortsoft.pf4j.util.ZipFileFilter;
 public class DefaultPluginManager implements PluginManager {

 

 	private static final Logger log = LoggerFactory.getLogger(DefaultPluginManager.class);

-	

+

 	public static final String DEFAULT_PLUGINS_DIRECTORY = "plugins";

 	public static final String DEVELOPMENT_PLUGINS_DIRECTORY = "../plugins";

 

@@ -52,11 +53,11 @@ public class DefaultPluginManager implements PluginManager {
     private File pluginsDirectory;

 

     private ExtensionFinder extensionFinder;

-    

+

     private PluginDescriptorFinder pluginDescriptorFinder;

-    

+

     private PluginClasspath pluginClasspath;

-    

+

     /**

      * A map of plugins this manager is responsible for (the key is the 'pluginId').

      */

@@ -81,35 +82,35 @@ public class DefaultPluginManager implements PluginManager {
      * A list with resolved plugins (resolved dependency).

      */

     private List<PluginWrapper> resolvedPlugins;

-    

+

     /**

      * A list with started plugins.

      */

     private List<PluginWrapper> startedPlugins;

-    

+

     private List<String> enabledPlugins;

     private List<String> disabledPlugins;

-    

+

     /**

-     * A compound class loader of resolved plugins. 

+     * A compound class loader of resolved plugins.

      */

     protected CompoundClassLoader compoundClassLoader;

-    

+

     /**

      * Cache value for the runtime mode. No need to re-read it because it wont change at

 	 * runtime.

      */

     private RuntimeMode runtimeMode;

-    

+

     /**

      * The plugins directory is supplied by System.getProperty("pf4j.pluginsDir", "plugins").

      */

     public DefaultPluginManager() {

     	this.pluginsDirectory = createPluginsDirectory();

-    	

+

     	initialize();

     }

-    

+

     /**

      * Constructs DefaultPluginManager which the given plugins directory.

      *

@@ -118,7 +119,7 @@ public class DefaultPluginManager implements PluginManager {
      */

     public DefaultPluginManager(File pluginsDirectory) {

         this.pluginsDirectory = pluginsDirectory;

-        

+

         initialize();

     }

 

@@ -145,7 +146,7 @@ public class DefaultPluginManager implements PluginManager {
 	public List<PluginWrapper> getStartedPlugins() {

 		return startedPlugins;

 	}

-	

+

     /**

      * Start all active plugins.

      */

@@ -163,6 +164,34 @@ public class DefaultPluginManager implements PluginManager {
         }

     }

 

+	/**

+     * Start the specified plugin and it's dependencies.

+     */

+    @Override

+    public PluginState startPlugin(String pluginId) {

+    	if (!plugins.containsKey(pluginId)) {

+    		throw new IllegalArgumentException(String.format("Unknown pluginId %s", pluginId));

+    	}

+    	PluginWrapper pluginWrapper = plugins.get(pluginId);

+    	PluginDescriptor pluginDescriptor = pluginWrapper.getDescriptor();

+    	if (pluginWrapper.getPluginState().equals(PluginState.STARTED)) {

+    		log.debug("Already started plugin '{}:{}'", pluginDescriptor.getPluginId(), pluginDescriptor.getVersion());

+    		return PluginState.STARTED;

+    	}

+    	for (PluginDependency dependency : pluginDescriptor.getDependencies()) {

+    		startPlugin(dependency.getPluginId());

+    	}

+    	try {

+    		log.info("Start plugin '{}:{}'", pluginDescriptor.getPluginId(), pluginDescriptor.getVersion());

+    		pluginWrapper.getPlugin().start();

+    		pluginWrapper.setPluginState(PluginState.STARTED);

+    		startedPlugins.add(pluginWrapper);

+    	} catch (PluginException e) {

+    		log.error(e.getMessage(), e);

+    	}

+    	return pluginWrapper.getPluginState();

+    }

+

     /**

      * Stop all active plugins.

      */

@@ -170,11 +199,15 @@ public class DefaultPluginManager implements PluginManager {
     public void stopPlugins() {

     	// stop started plugins in reverse order

     	Collections.reverse(startedPlugins);

-        for (PluginWrapper pluginWrapper : startedPlugins) {

+    	Iterator<PluginWrapper> itr = startedPlugins.iterator();

+        while (itr.hasNext()) {

+        	PluginWrapper pluginWrapper = itr.next();

+        	PluginDescriptor pluginDescriptor = pluginWrapper.getDescriptor();

             try {

-            	log.info("Stop plugin '{}'", pluginWrapper.getDescriptor().getPluginId());

+            	log.info("Stop plugin '{}:{}'", pluginDescriptor.getPluginId(), pluginDescriptor.getVersion());

             	pluginWrapper.getPlugin().stop();

             	pluginWrapper.setPluginState(PluginState.STOPPED);

+            	itr.remove();

 			} catch (PluginException e) {

 				log.error(e.getMessage(), e);

 			}

@@ -182,6 +215,34 @@ public class DefaultPluginManager implements PluginManager {
     }

 

     /**

+     * Stop the specified plugin and it's dependencies.

+     */

+    @Override

+    public PluginState stopPlugin(String pluginId) {

+    	if (!plugins.containsKey(pluginId)) {

+    		throw new IllegalArgumentException(String.format("Unknown pluginId %s", pluginId));

+    	}

+    	PluginWrapper pluginWrapper = plugins.get(pluginId);

+    	PluginDescriptor pluginDescriptor = pluginWrapper.getDescriptor();

+    	if (pluginWrapper.getPluginState().equals(PluginState.STOPPED)) {

+    		log.debug("Already stopped plugin '{}:{}'", pluginDescriptor.getPluginId(), pluginDescriptor.getVersion());

+    		return PluginState.STOPPED;

+    	}

+    	for (PluginDependency dependency : pluginDescriptor.getDependencies()) {

+    		stopPlugin(dependency.getPluginId());

+    	}

+    	try {

+    		log.info("Stop plugin '{}:{}'", pluginDescriptor.getPluginId(), pluginDescriptor.getVersion());

+    		pluginWrapper.getPlugin().stop();

+    		pluginWrapper.setPluginState(PluginState.STOPPED);

+    		startedPlugins.remove(pluginWrapper);

+    	} catch (PluginException e) {

+    		log.error(e.getMessage(), e);

+    	}

+    	return pluginWrapper.getPluginState();

+    }

+

+    /**

      * Load plugins.

      */

     @Override

@@ -233,6 +294,45 @@ public class DefaultPluginManager implements PluginManager {
 		}

     }

 

+    @Override

+    public boolean unloadPlugin(String pluginId) {

+    	try {

+    		PluginState state = stopPlugin(pluginId);

+    		if (!PluginState.STOPPED.equals(state)) {

+    			return false;

+    		}

+

+    		PluginWrapper pluginWrapper = plugins.get(pluginId);

+    		PluginDescriptor descriptor = pluginWrapper.getDescriptor();

+    		List<PluginDependency> dependencies = descriptor.getDependencies();

+    		for (PluginDependency dependency : dependencies) {

+    			if (!unloadPlugin(dependency.getPluginId())) {

+    				return false;

+    			}

+    		}

+

+    		// remove the plugin

+    		plugins.remove(pluginId);

+    		resolvedPlugins.remove(pluginWrapper);

+    		pathToIdMap.remove(pluginWrapper.getPluginPath());

+

+    		// remove the classloader

+    		if (pluginClassLoaders.containsKey(pluginId)) {

+    			PluginClassLoader classLoader = pluginClassLoaders.remove(pluginId);

+    			compoundClassLoader.removeLoader(classLoader);

+    			try {

+    				classLoader.close();

+    			} catch (IOException e) {

+    				log.error(e.getMessage(), e);

+    			}

+    		}

+    		return true;

+    	} catch (IllegalArgumentException e) {

+    		// ignore not found exceptions because this method is recursive

+    	}

+    	return false;

+    }

+

     /**

      * Get plugin class loader for this path.

      */

@@ -248,24 +348,24 @@ public class DefaultPluginManager implements PluginManager {
 		for (ExtensionWrapper<T> extensionWrapper : extensionsWrapper) {

 			extensions.add(extensionWrapper.getInstance());

 		}

-		

+

 		return extensions;

 	}

-	

+

     @Override

 	public RuntimeMode getRuntimeMode() {

     	if (runtimeMode == null) {

-        	// retrieves the runtime mode from system  

+        	// retrieves the runtime mode from system

         	String modeAsString = System.getProperty("pf4j.mode", RuntimeMode.DEPLOYMENT.toString());

         	runtimeMode = RuntimeMode.byName(modeAsString);

 

         	log.info("PF4J runtime mode is '{}'", runtimeMode);

 

     	}

-    	

+

 		return runtimeMode;

 	}

-	

+

     /**

      * Retrieves the {@link PluginWrapper} that loaded the given class 'clazz'.

      */

@@ -276,63 +376,63 @@ public class DefaultPluginManager implements PluginManager {
             	return plugin;

             }

         }

-        

+

         return null;

     }

 

 	/**

-	 * Add the possibility to override the PluginDescriptorFinder. 

-	 * By default if getRuntimeMode() returns RuntimeMode.DEVELOPMENT than a 

-	 * PropertiesPluginDescriptorFinder is returned else this method returns 

+	 * Add the possibility to override the PluginDescriptorFinder.

+	 * By default if getRuntimeMode() returns RuntimeMode.DEVELOPMENT than a

+	 * PropertiesPluginDescriptorFinder is returned else this method returns

 	 * DefaultPluginDescriptorFinder.

 	 */

     protected PluginDescriptorFinder createPluginDescriptorFinder() {

     	if (RuntimeMode.DEVELOPMENT.equals(getRuntimeMode())) {

     		return new PropertiesPluginDescriptorFinder();

     	}

-    	

+

     	return new DefaultPluginDescriptorFinder(pluginClasspath);

     }

 

     /**

-     * Add the possibility to override the ExtensionFinder. 

+     * Add the possibility to override the ExtensionFinder.

      */

     protected ExtensionFinder createExtensionFinder() {

     	return new DefaultExtensionFinder(compoundClassLoader);

     }

 

     /**

-     * Add the possibility to override the PluginClassPath. 

-     * By default if getRuntimeMode() returns RuntimeMode.DEVELOPMENT than a 

-	 * DevelopmentPluginClasspath is returned else this method returns 

+     * Add the possibility to override the PluginClassPath.

+     * By default if getRuntimeMode() returns RuntimeMode.DEVELOPMENT than a

+	 * DevelopmentPluginClasspath is returned else this method returns

 	 * PluginClasspath.

      */

     protected PluginClasspath createPluginClasspath() {

     	if (RuntimeMode.DEVELOPMENT.equals(getRuntimeMode())) {

     		return new DevelopmentPluginClasspath();

     	}

-    	

+

     	return new PluginClasspath();

     }

-    

+

     protected boolean isPluginDisabled(String pluginId) {

     	if (enabledPlugins.isEmpty()) {

     		return disabledPlugins.contains(pluginId);

     	}

-    	

+

     	return !enabledPlugins.contains(pluginId);

     }

-    

+

     protected FileFilter createHiddenPluginFilter() {

     	return new HiddenFilter();

     }

-    

+

     /**

      * Add the possibility to override the plugins directory.

      * If a "pf4j.pluginsDir" system property is defined than this method returns

      * that directory.

-     * If getRuntimeMode() returns RuntimeMode.DEVELOPMENT than a 

-	 * DEVELOPMENT_PLUGINS_DIRECTORY ("../plugins") is returned else this method returns 

+     * If getRuntimeMode() returns RuntimeMode.DEVELOPMENT than a

+	 * DEVELOPMENT_PLUGINS_DIRECTORY ("../plugins") is returned else this method returns

 	 * DEFAULT_PLUGINS_DIRECTORY ("plugins").

      * @return

      */

@@ -345,10 +445,10 @@ public class DefaultPluginManager implements PluginManager {
     			pluginsDir = DEFAULT_PLUGINS_DIRECTORY;

     		}

     	}

-    	

+

     	return new File(pluginsDir);

     }

-    

+

 	private void initialize() {

 		plugins = new HashMap<String, PluginWrapper>();

         pluginClassLoaders = new HashMap<String, PluginClassLoader>();

@@ -358,7 +458,7 @@ public class DefaultPluginManager implements PluginManager {
         startedPlugins = new ArrayList<PluginWrapper>();

         disabledPlugins = new ArrayList<String>();

         compoundClassLoader = new CompoundClassLoader();

-        

+

         pluginClasspath = createPluginClasspath();

         pluginDescriptorFinder = createPluginDescriptorFinder();

         extensionFinder = createExtensionFinder();

@@ -367,7 +467,7 @@ public class DefaultPluginManager implements PluginManager {
         	// create a list with plugin identifiers that should be only accepted by this manager (whitelist from plugins/enabled.txt file)

         	enabledPlugins = FileUtils.readLines(new File(pluginsDirectory, "enabled.txt"), true);

         	log.info("Enabled plugins: {}", enabledPlugins);

-        	

+

         	// create a list with plugin identifiers that should not be accepted by this manager (blacklist from plugins/disabled.txt file)

         	disabledPlugins = FileUtils.readLines(new File(pluginsDirectory, "disabled.txt"), true);

         	log.info("Disabled plugins: {}", disabledPlugins);

@@ -406,7 +506,7 @@ public class DefaultPluginManager implements PluginManager {
         PluginLoader pluginLoader = new PluginLoader(this, pluginDescriptor, pluginDirectory, pluginClasspath);

         pluginLoader.load();

         log.debug("Loaded plugin '{}'", pluginPath);

-        

+

         // create the plugin wrapper

         log.debug("Creating wrapper for plugin '{}'", pluginPath);

         PluginWrapper pluginWrapper = new PluginWrapper(pluginDescriptor, pluginPath, pluginLoader.getPluginClassLoader());

@@ -456,5 +556,5 @@ public class DefaultPluginManager implements PluginManager {
         	log.info("Plugin '{}' resolved", pluginWrapper.getDescriptor().getPluginId());

         }

 	}

-	

+

 }

diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/PluginManager.java b/pf4j/src/main/java/ro/fortsoft/pf4j/PluginManager.java
index 7c78b89..6ffe4cf 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/PluginManager.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/PluginManager.java
@@ -1,11 +1,11 @@
 /*
  * Copyright 2012 Decebal Suiu
- * 
+ *
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
  * the License. You may obtain a copy of the License in the LICENSE file, or 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.
@@ -36,7 +36,7 @@ public interface PluginManager {
 	 * Retrieves all unresolved plugins (with unresolved dependency).
 	 */
 	public List<PluginWrapper> getUnresolvedPlugins();
-	
+
     /**
      * Retrieves all started plugins.
      */
@@ -53,17 +53,39 @@ public interface PluginManager {
     public void startPlugins();
 
     /**
+     * Start the specified plugin and it's dependencies.
+     *
+     * @return the plugin state
+     */
+    public PluginState startPlugin(String pluginId);
+
+    /**
      * Stop all active plugins.
      */
     public void stopPlugins();
 
+    /**
+     * Stop the specified plugin and it's dependencies.
+     *
+     * @return the plugin state
+     */
+    public PluginState stopPlugin(String pluginId);
+
+    /**
+     * Unload a plugin.
+     *
+     * @param pluginId
+     * @return true if the plugin was unloaded
+     */
+    public boolean unloadPlugin(String pluginId);
+
 	public PluginClassLoader getPluginClassLoader(String pluginId);
 
 	public <T> List<T> getExtensions(Class<T> type);
-	
+
 	/**
 	 * The runtime mode. Must currently be either DEVELOPMENT or DEPLOYMENT.
 	 */
 	public RuntimeMode getRuntimeMode();
-	
+
 }
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/util/CompoundClassLoader.java b/pf4j/src/main/java/ro/fortsoft/pf4j/util/CompoundClassLoader.java
index f5c5df4..426b2a3 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/util/CompoundClassLoader.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/util/CompoundClassLoader.java
@@ -1,11 +1,11 @@
 /*
  * Copyright 2012 Decebal Suiu
- * 
+ *
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
  * the License. You may obtain a copy of the License in the LICENSE file, or 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.
@@ -23,7 +23,7 @@ import java.util.Set;
 
 /**
  * A class loader that has multiple loaders and uses them for loading classes and resources.
- * 
+ *
  * @author Decebal Suiu
  */
 public class CompoundClassLoader extends ClassLoader {
@@ -34,6 +34,10 @@ public class CompoundClassLoader extends ClassLoader {
 		loaders.add(loader);
 	}
 
+	public void removeLoader(ClassLoader loader) {
+		loaders.remove(loader);
+	}
+
 	@Override
 	public Class<?> findClass(String name) throws ClassNotFoundException {
 		for (ClassLoader loader : loaders) {
@@ -43,7 +47,7 @@ public class CompoundClassLoader extends ClassLoader {
 				// try next
 			}
 		}
-		
+
 		throw new ClassNotFoundException(name);
 	}
 
@@ -55,7 +59,7 @@ public class CompoundClassLoader extends ClassLoader {
 				return url;
 			}
 		}
-		
+
 		return null;
 	}
 
@@ -65,8 +69,8 @@ public class CompoundClassLoader extends ClassLoader {
 		for (ClassLoader loader : loaders) {
 			resources.addAll(Collections.list(loader.getResources(name)));
 		}
-		
+
 		return Collections.enumeration(resources);
 	}
-	
+
 }