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.network;
018
019import java.io.IOException;
020import java.util.ArrayList;
021import java.util.Arrays;
022import java.util.Iterator;
023import java.util.List;
024import org.apache.activemq.command.BrokerId;
025import org.apache.activemq.command.ConsumerId;
026import org.apache.activemq.command.ConsumerInfo;
027import org.apache.activemq.filter.DestinationFilter;
028import org.apache.activemq.transport.Transport;
029import org.slf4j.Logger;
030import org.slf4j.LoggerFactory;
031
032/**
033 * Consolidates subscriptions
034 * 
035 * 
036 */
037public class ConduitBridge extends DemandForwardingBridge {
038    private static final Logger LOG = LoggerFactory.getLogger(ConduitBridge.class);
039
040    /**
041     * Constructor
042     * 
043     * @param localBroker
044     * @param remoteBroker
045     */
046    public ConduitBridge(NetworkBridgeConfiguration configuration, Transport localBroker, Transport remoteBroker) {
047        super(configuration, localBroker, remoteBroker);
048    }
049
050    @Override
051    protected DemandSubscription createDemandSubscription(ConsumerInfo info) throws IOException {
052        if (addToAlreadyInterestedConsumers(info)) {
053            return null; // don't want this subscription added
054        }
055        //add our original id to ourselves
056        info.addNetworkConsumerId(info.getConsumerId());
057        info.setSelector(null);
058        return doCreateDemandSubscription(info);
059    }
060    
061    protected boolean checkPaths(BrokerId[] first, BrokerId[] second) {
062        if (first == null || second == null)
063                        return true;
064                if (Arrays.equals(first, second))
065                        return true;
066                if (first[0].equals(second[0])
067                                && first[first.length - 1].equals(second[second.length - 1]))
068                        return false;
069                else
070                        return true;
071    }
072
073    protected boolean addToAlreadyInterestedConsumers(ConsumerInfo info) {
074        // search through existing subscriptions and see if we have a match
075        boolean matched = false;
076        for (Iterator i = subscriptionMapByLocalId.values().iterator(); i.hasNext();) {
077            DemandSubscription ds = (DemandSubscription)i.next();
078            DestinationFilter filter = DestinationFilter.parseFilter(ds.getLocalInfo().getDestination());
079            if (filter.matches(info.getDestination())) {
080                if (LOG.isDebugEnabled()) {
081                    LOG.debug(configuration.getBrokerName() + " matched (add interest) to exsting sub for: " + ds.getRemoteInfo()
082                            + " with sub: " + info.getConsumerId());
083                }
084                // add the interest in the subscription
085                // ds.add(ds.getRemoteInfo().getConsumerId());
086                if (checkPaths(info.getBrokerPath(), ds.getRemoteInfo().getBrokerPath())) {
087                        ds.add(info.getConsumerId());
088                }
089                matched = true;
090                // continue - we want interest to any existing
091                // DemandSubscriptions
092            }
093        }
094        return matched;
095    }
096
097    @Override
098    protected void removeDemandSubscription(ConsumerId id) throws IOException {
099        List<DemandSubscription> tmpList = new ArrayList<DemandSubscription>();
100
101        for (Iterator i = subscriptionMapByLocalId.values().iterator(); i.hasNext();) {
102            DemandSubscription ds = (DemandSubscription)i.next();
103            if (ds.remove(id)) {
104                if (LOG.isDebugEnabled()) {
105                    LOG.debug(configuration.getBrokerName() + " removing interest in sub on " + localBroker + " from " + remoteBrokerName + " : sub: " + id  + " existing matched sub: " + ds.getRemoteInfo());
106                }
107            }
108            if (ds.isEmpty()) {
109                tmpList.add(ds);
110            }
111        }
112        for (Iterator<DemandSubscription> i = tmpList.iterator(); i.hasNext();) {
113            DemandSubscription ds = i.next();
114            removeSubscription(ds);
115            if (LOG.isDebugEnabled()) {
116                LOG.debug(configuration.getBrokerName() + " removing sub on " + localBroker + " from " + remoteBrokerName + " :  " + ds.getRemoteInfo());
117            }
118        }
119
120    }
121
122}