001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.activemq.transport.udp;
018    
019    import java.nio.ByteBuffer;
020    import java.util.ArrayList;
021    import java.util.List;
022    
023    /**
024     * A default implementation of {@link BufferPool} which keeps a pool of direct
025     * byte buffers.
026     * 
027     * 
028     */
029    public class DefaultBufferPool extends SimpleBufferPool implements ByteBufferPool {
030    
031        private List<ByteBuffer> buffers = new ArrayList<ByteBuffer>();
032        private Object lock = new Object();
033    
034        public DefaultBufferPool() {
035            super(true);
036        }
037    
038        public DefaultBufferPool(boolean useDirect) {
039            super(useDirect);
040        }
041    
042        public synchronized ByteBuffer borrowBuffer() {
043            synchronized (lock) {
044                int size = buffers.size();
045                if (size > 0) {
046                    return buffers.remove(size - 1);
047                }
048            }
049            return createBuffer();
050        }
051    
052        public void returnBuffer(ByteBuffer buffer) {
053            synchronized (lock) {
054                buffers.add(buffer);
055            }
056        }
057    
058        public void start() throws Exception {
059        }
060    
061        public void stop() throws Exception {
062            synchronized (lock) {
063                /*
064                 * for (Iterator iter = buffers.iterator(); iter.hasNext();) {
065                 * ByteBuffer buffer = (ByteBuffer) iter.next(); }
066                 */
067                buffers.clear();
068            }
069        }
070    
071    }