| /** |
| * 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.activemq.transport.reliable; |
| |
| import java.io.IOException; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * |
| * |
| */ |
| public class DefaultReplayBuffer implements ReplayBuffer { |
| |
| private static final Logger LOG = LoggerFactory.getLogger(DefaultReplayBuffer.class); |
| |
| private final int size; |
| private ReplayBufferListener listener; |
| private Map<Integer, Object> map; |
| private int lowestCommandId = 1; |
| private Object lock = new Object(); |
| |
| public DefaultReplayBuffer(int size) { |
| this.size = size; |
| map = createMap(size); |
| } |
| |
| public void addBuffer(int commandId, Object buffer) { |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Adding command ID: " + commandId + " to replay buffer: " + this + " object: " + buffer); |
| } |
| synchronized (lock) { |
| int max = size - 1; |
| while (map.size() >= max) { |
| // lets find things to evict |
| Object evictedBuffer = map.remove(Integer.valueOf(++lowestCommandId)); |
| onEvictedBuffer(lowestCommandId, evictedBuffer); |
| } |
| map.put(Integer.valueOf(commandId), buffer); |
| } |
| } |
| |
| public void setReplayBufferListener(ReplayBufferListener bufferPoolAdapter) { |
| this.listener = bufferPoolAdapter; |
| } |
| |
| public void replayMessages(int fromCommandId, int toCommandId, Replayer replayer) throws IOException { |
| if (replayer == null) { |
| throw new IllegalArgumentException("No Replayer parameter specified"); |
| } |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Buffer: " + this + " replaying messages from: " + fromCommandId + " to: " + toCommandId); |
| } |
| for (int i = fromCommandId; i <= toCommandId; i++) { |
| Object buffer = null; |
| synchronized (lock) { |
| buffer = map.get(Integer.valueOf(i)); |
| } |
| replayer.sendBuffer(i, buffer); |
| } |
| } |
| |
| protected Map<Integer, Object> createMap(int maximumSize) { |
| return new HashMap<Integer, Object>(maximumSize); |
| } |
| |
| protected void onEvictedBuffer(int commandId, Object buffer) { |
| if (listener != null) { |
| listener.onBufferDiscarded(commandId, buffer); |
| } |
| } |
| } |