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 */
017package org.apache.activemq.broker.region.virtual;
018
019import org.apache.activemq.broker.ProducerBrokerExchange;
020import org.apache.activemq.broker.region.Destination;
021import org.apache.activemq.broker.region.DestinationFilter;
022import org.apache.activemq.command.ActiveMQDestination;
023import org.apache.activemq.command.ActiveMQQueue;
024import org.apache.activemq.command.Message;
025import org.apache.activemq.util.LRUCache;
026
027/**
028 * A Destination which implements <a
029 * href="http://activemq.org/site/virtual-destinations.html">Virtual Topic</a>
030 * 
031 * 
032 */
033public class VirtualTopicInterceptor extends DestinationFilter {
034
035    private String prefix;
036    private String postfix;
037    private boolean local;
038    private LRUCache<ActiveMQDestination,ActiveMQQueue> cache = new LRUCache<ActiveMQDestination,ActiveMQQueue>();
039
040    public VirtualTopicInterceptor(Destination next, String prefix, String postfix, boolean local) {
041        super(next);
042        this.prefix = prefix;
043        this.postfix = postfix;
044        this.local = local;
045    }
046
047    public void send(ProducerBrokerExchange context, Message message) throws Exception {
048        if (!message.isAdvisory() && !(local && message.getBrokerPath() != null)) {
049            ActiveMQDestination queueConsumers = getQueueConsumersWildcard(message.getDestination());
050            send(context, message, queueConsumers);
051        }
052        super.send(context, message);
053    }
054
055    protected ActiveMQDestination getQueueConsumersWildcard(ActiveMQDestination original) {
056        ActiveMQQueue queue;
057        synchronized(cache){
058            queue = cache.get(original);
059            if (queue==null){
060                queue = new ActiveMQQueue(prefix + original.getPhysicalName() + postfix);
061                cache.put(original,queue);
062            }
063        }
064        return queue;
065    }
066}