| package org.apache.velocity.runtime.resource; |
| |
| /* |
| * 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.util.Collections; |
| import java.util.HashMap; |
| import java.util.Hashtable; |
| import java.util.Map; |
| import java.util.Iterator; |
| |
| import org.apache.commons.collections.map.LRUMap; |
| import org.apache.velocity.runtime.RuntimeConstants; |
| import org.apache.velocity.runtime.RuntimeServices; |
| import java.util.concurrent.ConcurrentHashMap; |
| |
| /** |
| * Default implementation of the resource cache for the default |
| * ResourceManager. The cache uses a <i>least recently used</i> (LRU) |
| * algorithm, with a maximum size specified via the |
| * <code>resource.manager.cache.size</code> property (idenfied by the |
| * {@link |
| * org.apache.velocity.runtime.RuntimeConstants#RESOURCE_MANAGER_DEFAULTCACHE_SIZE} |
| * constant). This property get be set to <code>0</code> or less for |
| * a greedy, unbounded cache (the behavior from pre-v1.5). |
| * |
| * @author <a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a> |
| * @author <a href="mailto:dlr@finemaltcoding.com">Daniel Rall</a> |
| * @version $Id$ |
| */ |
| public class ResourceCacheImpl implements ResourceCache |
| { |
| /** |
| * Cache storage, assumed to be thread-safe. |
| */ |
| protected Map cache = new ConcurrentHashMap(512, 0.5f, 30); |
| |
| /** |
| * Runtime services, generally initialized by the |
| * <code>initialize()</code> method. |
| */ |
| protected RuntimeServices rsvc = null; |
| |
| /** |
| * @see org.apache.velocity.runtime.resource.ResourceCache#initialize(org.apache.velocity.runtime.RuntimeServices) |
| */ |
| public void initialize( RuntimeServices rs ) |
| { |
| rsvc = rs; |
| |
| int maxSize = |
| rsvc.getInt(RuntimeConstants.RESOURCE_MANAGER_DEFAULTCACHE_SIZE, 89); |
| if (maxSize > 0) |
| { |
| // Create a whole new Map here to avoid hanging on to a |
| // handle to the unsynch'd LRUMap for our lifetime. |
| Map lruCache = Collections.synchronizedMap(new LRUMap(maxSize)); |
| lruCache.putAll(cache); |
| cache = lruCache; |
| } |
| rsvc.getLog().debug("ResourceCache: initialized ("+this.getClass()+") with "+ |
| cache.getClass()+" cache map."); |
| } |
| |
| /** |
| * @see org.apache.velocity.runtime.resource.ResourceCache#get(java.lang.Object) |
| */ |
| public Resource get( Object key ) |
| { |
| return (Resource) cache.get( key ); |
| } |
| |
| /** |
| * @see org.apache.velocity.runtime.resource.ResourceCache#put(java.lang.Object, org.apache.velocity.runtime.resource.Resource) |
| */ |
| public Resource put( Object key, Resource value ) |
| { |
| return (Resource) cache.put( key, value ); |
| } |
| |
| /** |
| * @see org.apache.velocity.runtime.resource.ResourceCache#remove(java.lang.Object) |
| */ |
| public Resource remove( Object key ) |
| { |
| return (Resource) cache.remove( key ); |
| } |
| |
| /** |
| * @see org.apache.velocity.runtime.resource.ResourceCache#enumerateKeys() |
| */ |
| public Iterator enumerateKeys() |
| { |
| return cache.keySet().iterator(); |
| } |
| } |
| |