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;
018    
019    import javax.jms.JMSException;
020    
021    import org.apache.activemq.advisory.AdvisorySupport;
022    import org.apache.activemq.command.ActiveMQDestination;
023    import org.apache.activemq.command.ActiveMQTempDestination;
024    import org.apache.activemq.command.ConsumerId;
025    import org.apache.activemq.command.ConsumerInfo;
026    import org.apache.activemq.command.DataStructure;
027    import org.apache.activemq.command.DestinationInfo;
028    import org.apache.activemq.command.MessageAck;
029    import org.apache.activemq.command.MessageDispatch;
030    import org.slf4j.Logger;
031    import org.slf4j.LoggerFactory;
032    
033    public class AdvisoryConsumer implements ActiveMQDispatcher {
034        private static final transient Logger LOG = LoggerFactory.getLogger(AdvisoryConsumer.class);
035    
036        int deliveredCounter;
037    
038        private final ActiveMQConnection connection;
039        private ConsumerInfo info;
040        private boolean closed;
041    
042        public AdvisoryConsumer(ActiveMQConnection connection, ConsumerId consumerId) throws JMSException {
043            this.connection = connection;
044            info = new ConsumerInfo(consumerId);
045            info.setDestination(AdvisorySupport.TEMP_DESTINATION_COMPOSITE_ADVISORY_TOPIC);
046            info.setPrefetchSize(1000);
047            info.setNoLocal(true);
048    
049            this.connection.addDispatcher(info.getConsumerId(), this);
050            this.connection.syncSendPacket(this.info);
051        }
052    
053        public synchronized void dispose() {
054            if (!closed) {
055                try {
056                    this.connection.asyncSendPacket(info.createRemoveCommand());
057                } catch (JMSException e) {
058                    LOG.debug("Failed to send remove command: " + e, e);
059                }
060                this.connection.removeDispatcher(info.getConsumerId());
061                closed = true;
062            }
063        }
064    
065        public void dispatch(MessageDispatch md) {
066    
067            // Auto ack messages when we reach 75% of the prefetch
068            deliveredCounter++;
069            if (deliveredCounter > (0.75 * info.getPrefetchSize())) {
070                try {
071                    MessageAck ack = new MessageAck(md, MessageAck.STANDARD_ACK_TYPE, deliveredCounter);
072                    connection.asyncSendPacket(ack);
073                    deliveredCounter = 0;
074                } catch (JMSException e) {
075                    connection.onClientInternalException(e);
076                }
077            }
078    
079            DataStructure o = md.getMessage().getDataStructure();
080            if (o != null && o.getClass() == DestinationInfo.class) {
081                processDestinationInfo((DestinationInfo)o);
082            } else {
083                //This can happen across networks
084                if (LOG.isDebugEnabled()) {
085                    LOG.debug("Unexpected message was dispatched to the AdvisoryConsumer: "+md);
086                }
087            }
088    
089        }
090    
091        private void processDestinationInfo(DestinationInfo dinfo) {
092            ActiveMQDestination dest = dinfo.getDestination();
093            if (!dest.isTemporary()) {
094                return;
095            }
096    
097            ActiveMQTempDestination tempDest = (ActiveMQTempDestination)dest;
098            if (dinfo.getOperationType() == DestinationInfo.ADD_OPERATION_TYPE) {
099                connection.activeTempDestinations.put(tempDest, tempDest);
100            } else if (dinfo.getOperationType() == DestinationInfo.REMOVE_OPERATION_TYPE) {
101                connection.activeTempDestinations.remove(tempDest);
102            }
103        }
104    
105    }