ThreadLocalCacheMap.java

/*
 * 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.
 */

package org.apache.sling.commons.cache.impl;

import java.util.HashMap;
import java.util.Map;

import org.apache.sling.commons.cache.api.Cache;

/**
 * Represents a Cache stored on the thread, used in the request thread and in
 * other threads. When used in Threads there is a potential for memory leaks as
 * perm space is not cleaned up. This will be caused by references to
 * classloaders being in the Map, and keeping the classloaders open.
 */
public class ThreadLocalCacheMap extends ThreadLocal<Map<String, Cache<?>>> {
	/**
	 * {@inheritDoc}
	 * 
	 * @see java.lang.ThreadLocal#initialValue()
	 */
	@Override
	protected Map<String, Cache<?>> initialValue() {
		return new HashMap<String, Cache<?>>();
	}
}