trunk/activemq-core/src/main/java/org/apache/activemq/network/DemandForwardingBridge.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.activemq.network;

import java.io.IOException;

import org.apache.activemq.command.BrokerId;
import org.apache.activemq.command.BrokerInfo;
import org.apache.activemq.command.Command;
import org.apache.activemq.command.ConsumerInfo;
import org.apache.activemq.command.NetworkBridgeFilter;
import org.apache.activemq.transport.Transport;
import org.apache.activemq.util.ServiceSupport;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Forwards messages from the local broker to the remote broker based on demand.
 * 
 * @org.apache.xbean.XBean
 * 
 * 
 */
public class DemandForwardingBridge extends DemandForwardingBridgeSupport {
    private static final Logger LOG = LoggerFactory.getLogger(DemandForwardingBridge.class);

    protected final BrokerId remoteBrokerPath[] = new BrokerId[] {null};
    protected Object brokerInfoMutex = new Object();
    protected BrokerId remoteBrokerId;

    public DemandForwardingBridge(NetworkBridgeConfiguration configuration, Transport localBroker,
                                  Transport remoteBroker) {
        super(configuration, localBroker, remoteBroker);
    }

    protected void serviceRemoteBrokerInfo(Command command) throws IOException {
        synchronized (brokerInfoMutex) {
            BrokerInfo remoteBrokerInfo = (BrokerInfo)command;
            remoteBrokerId = remoteBrokerInfo.getBrokerId();
            remoteBrokerPath[0] = remoteBrokerId;
            remoteBrokerName = remoteBrokerInfo.getBrokerName();
            if (localBrokerId != null) {
                if (localBrokerId.equals(remoteBrokerId)) {
                    if (LOG.isTraceEnabled()) {
                        LOG.trace(configuration.getBrokerName() + " disconnecting remote loop back connection: " + remoteBrokerName);
                    }
                    ServiceSupport.dispose(this);
                }
            }
            if (LOG.isTraceEnabled()) {
                LOG.trace("counting down remoteBrokerNameKnownLatch with: " + command);
            }
            remoteBrokerNameKnownLatch.countDown();
        }
    }

    protected void addRemoteBrokerToBrokerPath(ConsumerInfo info) {
        info.setBrokerPath(appendToBrokerPath(info.getBrokerPath(), getRemoteBrokerPath()));
    }

    protected void serviceLocalBrokerInfo(Command command) throws InterruptedException {
        synchronized (brokerInfoMutex) {
            localBrokerId = ((BrokerInfo)command).getBrokerId();
            localBrokerPath[0] = localBrokerId;
            localBrokerIdKnownLatch.countDown();
            if (remoteBrokerId != null) {
                if (remoteBrokerId.equals(localBrokerId)) {
                    if (LOG.isTraceEnabled()) {
                        LOG.trace(configuration.getBrokerName() + " disconnecting local loop back connection.");
                    }
                    waitStarted();
                    ServiceSupport.dispose(this);
                }
            }
        }
    }

    protected NetworkBridgeFilter createNetworkBridgeFilter(ConsumerInfo info) throws IOException {
        return new NetworkBridgeFilter(remoteBrokerPath[0], configuration.getNetworkTTL());
    }

    protected BrokerId[] getRemoteBrokerPath() {
        return remoteBrokerPath;
    }
}