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.network;
018    
019    import java.io.IOException;
020    import java.util.ArrayList;
021    import java.util.Arrays;
022    import java.util.Iterator;
023    import java.util.List;
024    import org.apache.activemq.command.BrokerId;
025    import org.apache.activemq.command.ConsumerId;
026    import org.apache.activemq.command.ConsumerInfo;
027    import org.apache.activemq.filter.DestinationFilter;
028    import org.apache.activemq.transport.Transport;
029    import org.slf4j.Logger;
030    import org.slf4j.LoggerFactory;
031    
032    /**
033     * Consolidates subscriptions
034     * 
035     * 
036     */
037    public 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    }