src/main/java/org/apache/sling/scripting/core/impl/ScriptCacheImpl.java - sling-org-apache-sling-scripting-core - Git at Google

 /*******************************************************************************
  * 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
  * <p/>
  * http://www.apache.org/licenses/LICENSE-2.0
  * <p/>
  * 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.apache.sling.scripting.core.impl;

 import java.lang.ref.SoftReference;
 import java.util.Arrays;
 import java.util.Dictionary;
 import java.util.HashSet;
 import java.util.Hashtable;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;

 import javax.script.Compilable;
 import javax.script.ScriptEngine;
 import javax.script.ScriptEngineFactory;

 import org.apache.sling.api.resource.ResourceResolverFactory;
 import org.apache.sling.api.resource.observation.ExternalResourceChangeListener;
 import org.apache.sling.api.resource.observation.ResourceChange;
 import org.apache.sling.api.resource.observation.ResourceChange.ChangeType;
 import org.apache.sling.api.resource.observation.ResourceChangeListener;
 import org.apache.sling.commons.threads.ThreadPool;
 import org.apache.sling.commons.threads.ThreadPoolManager;
 import org.apache.sling.scripting.api.CachedScript;
 import org.apache.sling.scripting.api.ScriptCache;
 import org.apache.sling.scripting.core.impl.helper.CachingMap;
 import org.apache.sling.scripting.core.impl.jsr223.SlingScriptEngineManager;
 import org.apache.sling.serviceusermapping.ServiceUserMapped;
 import org.jetbrains.annotations.NotNull;
 import org.osgi.framework.BundleContext;
 import org.osgi.framework.Constants;
 import org.osgi.framework.ServiceRegistration;
 import org.osgi.service.component.annotations.Activate;
 import org.osgi.service.component.annotations.Component;
 import org.osgi.service.component.annotations.Deactivate;
 import org.osgi.service.component.annotations.Reference;
 import org.osgi.service.event.Event;
 import org.osgi.service.event.EventConstants;
 import org.osgi.service.event.EventHandler;
 import org.osgi.service.metatype.annotations.Designate;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 @Component(
     service = {ScriptCache.class, EventHandler.class},
     property = {
             Constants.SERVICE_VENDOR + "=The Apache Software Foundation",
             EventConstants.EVENT_TOPIC + "=org/apache/sling/scripting/core/impl/jsr223/SlingScriptEngineManager/*"
     }
 )
 @Designate(
     ocd = ScriptCacheImplConfiguration.class
 )
 /**
  * The {@code ScriptCache} stores information about {@link CompiledScript} instances evaluated by various {@link ScriptEngine}s that
  * implement the {@link Compilable} interface.
  */
 public class ScriptCacheImpl implements ScriptCache, ResourceChangeListener, ExternalResourceChangeListener, EventHandler {

     private final Logger logger = LoggerFactory.getLogger(ScriptCacheImpl.class);

     public static final int DEFAULT_CACHE_SIZE = 65536;

     private BundleContext bundleContext;
     private Map<String, SoftReference<CachedScript>> internalMap;
     private ServiceRegistration<ResourceChangeListener> resourceChangeListener;
     private Set<String> extensions = new HashSet<>();
     private String[] additionalExtensions = new String[]{};

     // use a static policy so that we can reconfigure the watched script files if the search paths are changed
     @Reference
     private ResourceResolverFactory rrf;

     @Reference
     private ThreadPoolManager threadPoolManager;

     @Reference
     private SlingScriptEngineManager slingScriptEngineManager;

     private ThreadPool threadPool;
     private final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock();
     private final Lock readLock = rwl.readLock();
     private final Lock writeLock = rwl.writeLock();
     private volatile boolean active = false;

     @Reference
     private ServiceUserMapped serviceUserMapped;

     public ScriptCacheImpl() {
         internalMap = new CachingMap<>(DEFAULT_CACHE_SIZE);
     }

     @Override
     public CachedScript getScript(String scriptPath) {
         readLock.lock();
         SoftReference<CachedScript> reference = null;
         try {
             reference = internalMap.get(scriptPath);
         } finally {
             readLock.unlock();
         }
         return reference != null ? reference.get() : null;
     }

     @Override
     public void putScript(CachedScript script) {
         writeLock.lock();
         try {
             SoftReference<CachedScript> reference = new SoftReference<>(script);
             internalMap.put(script.getScriptPath(), reference);
             logger.debug("Added script {} to script cache.", script.getScriptPath());
         } finally {
             writeLock.unlock();
         }
     }

     @Override
     public void clear() {
         writeLock.lock();
         try {
             internalMap.clear();
             logger.debug("Cleared script cache.");
         } finally {
             writeLock.unlock();
         }
     }

     @Override
     public boolean removeScript(String scriptPath) {
         writeLock.lock();
         try {
             SoftReference<CachedScript> reference = internalMap.remove(scriptPath);
             boolean result = reference != null;
             if (result) {
                 logger.debug("Removed script {} from script cache.", scriptPath);
             }
             return result;
         } finally {
             writeLock.unlock();
         }
     }

     @Override
     public void onChange(@NotNull List<ResourceChange> list) {
         for (final ResourceChange change : list) {
             Runnable eventTask = () -> {
                 String path = change.getPath();
                 writeLock.lock();
                 try {
                     final boolean removed = internalMap.remove(path) != null;
                     logger.debug("Detected script change for {} - removed entry from the cache.", path);
                     if ( !removed && change.getType() == ChangeType.REMOVED ) {
                         final String prefix = path + "/";
                         final Set<String> removal = new HashSet<>();
                         for(final Map.Entry<String, SoftReference<CachedScript>> entry : internalMap.entrySet()) {
                             if ( entry.getKey().startsWith(prefix) ) {
                                 removal.add(entry.getKey());
                             }
                         }
                         for(final String key : removal) {
                             internalMap.remove(key);
                             logger.debug("Detected removal for {} - removed entry {} from the cache.", path, key);
                         }
                     }
                 } finally {
                     writeLock.unlock();
                 }
             };
             threadPool.execute(eventTask);
         }
     }

     protected Set<String> getCachedScripts() {
         readLock.lock();
         try {
             return internalMap.keySet();
         } finally {
             readLock.unlock();
         }
     }

     @Activate
     protected void activate(ScriptCacheImplConfiguration configuration, BundleContext bundleCtx) {
         threadPool = threadPoolManager.get("Script Cache Thread Pool");
         bundleContext = bundleCtx;
         additionalExtensions = configuration.org_apache_sling_scripting_cache_additional__extensions();
         int newMaxCacheSize = configuration.org_apache_sling_scripting_cache_size();
         if (newMaxCacheSize != DEFAULT_CACHE_SIZE) {
             // change the map only if there's a configuration change regarding the cache's max size
             CachingMap<CachedScript> newMap = new CachingMap<>(newMaxCacheSize);
             newMap.putAll(internalMap);
             internalMap = newMap;
         }
         active = true;
         configureCache();
     }

     private void configureCache() {
         writeLock.lock();
         try {
             if (active) {
                 if (resourceChangeListener != null) {
                     resourceChangeListener.unregister();
                     resourceChangeListener = null;
                 }
                 internalMap.clear();
                 if (additionalExtensions != null) {
                     extensions.addAll(Arrays.asList(additionalExtensions));
                 }
                 if (!extensions.isEmpty()) {
                     Set<String> globPatterns = new HashSet<>(extensions.size());
                     for (String extension : extensions) {
                         globPatterns.add("glob:**/*." + extension);
                     }
                     Dictionary<String, Object> resourceChangeListenerProperties = new Hashtable<>(); // NOSONAR
                     resourceChangeListenerProperties
                             .put(ResourceChangeListener.PATHS, globPatterns.toArray(new String[globPatterns.size()]));
                     resourceChangeListenerProperties.put(ResourceChangeListener.CHANGES,
                             new String[]{ResourceChange.ChangeType.CHANGED.name(), ResourceChange.ChangeType.REMOVED.name()});
                     resourceChangeListener =
                             bundleContext.registerService(
                                     ResourceChangeListener.class,
                                     this,
                                     resourceChangeListenerProperties
                             );
                 }
             }
         } finally {
             writeLock.unlock();
         }
     }

     @Deactivate
     protected void deactivate() {
         writeLock.lock();
         try {
             internalMap.clear();
             if (resourceChangeListener != null) {
                 resourceChangeListener.unregister();
                 resourceChangeListener = null;
             }
             if (threadPool != null) {
                 threadPoolManager.release(threadPool);
                 threadPool = null;
             }
             active = false;
         } finally {
             writeLock.unlock();
         }
     }

     @Override
     public void handleEvent(Event event) {
         clear();
         extensions.clear();
         for (ScriptEngineFactory factory :  slingScriptEngineManager.getEngineFactories()) {
             ScriptEngine scriptEngine = factory.getScriptEngine();
             if (scriptEngine instanceof Compilable) {
                 extensions.addAll(factory.getExtensions());
             }
         }
         configureCache();
     }
 }
	/*******************************************************************************
	* 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
	* <p/>
	* http://www.apache.org/licenses/LICENSE-2.0
	* <p/>
	* 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.apache.sling.scripting.core.impl;

	import java.lang.ref.SoftReference;
	import java.util.Arrays;
	import java.util.Dictionary;
	import java.util.HashSet;
	import java.util.Hashtable;
	import java.util.List;
	import java.util.Map;
	import java.util.Set;
	import java.util.concurrent.locks.Lock;
	import java.util.concurrent.locks.ReentrantReadWriteLock;

	import javax.script.Compilable;
	import javax.script.ScriptEngine;
	import javax.script.ScriptEngineFactory;

	import org.apache.sling.api.resource.ResourceResolverFactory;
	import org.apache.sling.api.resource.observation.ExternalResourceChangeListener;
	import org.apache.sling.api.resource.observation.ResourceChange;
	import org.apache.sling.api.resource.observation.ResourceChange.ChangeType;
	import org.apache.sling.api.resource.observation.ResourceChangeListener;
	import org.apache.sling.commons.threads.ThreadPool;
	import org.apache.sling.commons.threads.ThreadPoolManager;
	import org.apache.sling.scripting.api.CachedScript;
	import org.apache.sling.scripting.api.ScriptCache;
	import org.apache.sling.scripting.core.impl.helper.CachingMap;
	import org.apache.sling.scripting.core.impl.jsr223.SlingScriptEngineManager;
	import org.apache.sling.serviceusermapping.ServiceUserMapped;
	import org.jetbrains.annotations.NotNull;
	import org.osgi.framework.BundleContext;
	import org.osgi.framework.Constants;
	import org.osgi.framework.ServiceRegistration;
	import org.osgi.service.component.annotations.Activate;
	import org.osgi.service.component.annotations.Component;
	import org.osgi.service.component.annotations.Deactivate;
	import org.osgi.service.component.annotations.Reference;
	import org.osgi.service.event.Event;
	import org.osgi.service.event.EventConstants;
	import org.osgi.service.event.EventHandler;
	import org.osgi.service.metatype.annotations.Designate;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	@Component(
	service = {ScriptCache.class, EventHandler.class},
	property = {
	Constants.SERVICE_VENDOR + "=The Apache Software Foundation",
	EventConstants.EVENT_TOPIC + "=org/apache/sling/scripting/core/impl/jsr223/SlingScriptEngineManager/*"
	}
	)
	@Designate(
	ocd = ScriptCacheImplConfiguration.class
	)
	/**
	* The {@code ScriptCache} stores information about {@link CompiledScript} instances evaluated by various {@link ScriptEngine}s that
	* implement the {@link Compilable} interface.
	*/
	public class ScriptCacheImpl implements ScriptCache, ResourceChangeListener, ExternalResourceChangeListener, EventHandler {

	private final Logger logger = LoggerFactory.getLogger(ScriptCacheImpl.class);

	public static final int DEFAULT_CACHE_SIZE = 65536;

	private BundleContext bundleContext;
	private Map<String, SoftReference<CachedScript>> internalMap;
	private ServiceRegistration<ResourceChangeListener> resourceChangeListener;
	private Set<String> extensions = new HashSet<>();
	private String[] additionalExtensions = new String[]{};

	// use a static policy so that we can reconfigure the watched script files if the search paths are changed
	@Reference
	private ResourceResolverFactory rrf;

	@Reference
	private ThreadPoolManager threadPoolManager;

	@Reference
	private SlingScriptEngineManager slingScriptEngineManager;

	private ThreadPool threadPool;
	private final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock();
	private final Lock readLock = rwl.readLock();
	private final Lock writeLock = rwl.writeLock();
	private volatile boolean active = false;

	@Reference
	private ServiceUserMapped serviceUserMapped;

	public ScriptCacheImpl() {
	internalMap = new CachingMap<>(DEFAULT_CACHE_SIZE);
	}

	@Override
	public CachedScript getScript(String scriptPath) {
	readLock.lock();
	SoftReference<CachedScript> reference = null;
	try {
	reference = internalMap.get(scriptPath);
	} finally {
	readLock.unlock();
	}
	return reference != null ? reference.get() : null;
	}

	@Override
	public void putScript(CachedScript script) {
	writeLock.lock();
	try {
	SoftReference<CachedScript> reference = new SoftReference<>(script);
	internalMap.put(script.getScriptPath(), reference);
	logger.debug("Added script {} to script cache.", script.getScriptPath());
	} finally {
	writeLock.unlock();
	}
	}

	@Override
	public void clear() {
	writeLock.lock();
	try {
	internalMap.clear();
	logger.debug("Cleared script cache.");
	} finally {
	writeLock.unlock();
	}
	}

	@Override
	public boolean removeScript(String scriptPath) {
	writeLock.lock();
	try {
	SoftReference<CachedScript> reference = internalMap.remove(scriptPath);
	boolean result = reference != null;
	if (result) {
	logger.debug("Removed script {} from script cache.", scriptPath);
	}
	return result;
	} finally {
	writeLock.unlock();
	}
	}

	@Override
	public void onChange(@NotNull List<ResourceChange> list) {
	for (final ResourceChange change : list) {
	Runnable eventTask = () -> {
	String path = change.getPath();
	writeLock.lock();
	try {
	final boolean removed = internalMap.remove(path) != null;
	logger.debug("Detected script change for {} - removed entry from the cache.", path);
	if ( !removed && change.getType() == ChangeType.REMOVED ) {
	final String prefix = path + "/";
	final Set<String> removal = new HashSet<>();
	for(final Map.Entry<String, SoftReference<CachedScript>> entry : internalMap.entrySet()) {
	if ( entry.getKey().startsWith(prefix) ) {
	removal.add(entry.getKey());
	}
	}
	for(final String key : removal) {
	internalMap.remove(key);
	logger.debug("Detected removal for {} - removed entry {} from the cache.", path, key);
	}
	}
	} finally {
	writeLock.unlock();
	}
	};
	threadPool.execute(eventTask);
	}
	}

	protected Set<String> getCachedScripts() {
	readLock.lock();
	try {
	return internalMap.keySet();
	} finally {
	readLock.unlock();
	}
	}

	@Activate
	protected void activate(ScriptCacheImplConfiguration configuration, BundleContext bundleCtx) {
	threadPool = threadPoolManager.get("Script Cache Thread Pool");
	bundleContext = bundleCtx;
	additionalExtensions = configuration.org_apache_sling_scripting_cache_additional__extensions();
	int newMaxCacheSize = configuration.org_apache_sling_scripting_cache_size();
	if (newMaxCacheSize != DEFAULT_CACHE_SIZE) {
	// change the map only if there's a configuration change regarding the cache's max size
	CachingMap<CachedScript> newMap = new CachingMap<>(newMaxCacheSize);
	newMap.putAll(internalMap);
	internalMap = newMap;
	}
	active = true;
	configureCache();
	}

	private void configureCache() {
	writeLock.lock();
	try {
	if (active) {
	if (resourceChangeListener != null) {
	resourceChangeListener.unregister();
	resourceChangeListener = null;
	}
	internalMap.clear();
	if (additionalExtensions != null) {
	extensions.addAll(Arrays.asList(additionalExtensions));
	}
	if (!extensions.isEmpty()) {
	Set<String> globPatterns = new HashSet<>(extensions.size());
	for (String extension : extensions) {
	globPatterns.add("glob:*/." + extension);
	}
	Dictionary<String, Object> resourceChangeListenerProperties = new Hashtable<>(); // NOSONAR
	resourceChangeListenerProperties
	.put(ResourceChangeListener.PATHS, globPatterns.toArray(new String[globPatterns.size()]));
	resourceChangeListenerProperties.put(ResourceChangeListener.CHANGES,
	new String[]{ResourceChange.ChangeType.CHANGED.name(), ResourceChange.ChangeType.REMOVED.name()});
	resourceChangeListener =
	bundleContext.registerService(
	ResourceChangeListener.class,
	this,
	resourceChangeListenerProperties
	);
	}
	}
	} finally {
	writeLock.unlock();
	}
	}

	@Deactivate
	protected void deactivate() {
	writeLock.lock();
	try {
	internalMap.clear();
	if (resourceChangeListener != null) {
	resourceChangeListener.unregister();
	resourceChangeListener = null;
	}
	if (threadPool != null) {
	threadPoolManager.release(threadPool);
	threadPool = null;
	}
	active = false;
	} finally {
	writeLock.unlock();
	}
	}

	@Override
	public void handleEvent(Event event) {
	clear();
	extensions.clear();
	for (ScriptEngineFactory factory : slingScriptEngineManager.getEngineFactories()) {
	ScriptEngine scriptEngine = factory.getScriptEngine();
	if (scriptEngine instanceof Compilable) {
	extensions.addAll(factory.getExtensions());
	}
	}
	configureCache();
	}
	}