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.broker.region;
018    
019    import java.io.IOException;
020    import javax.jms.InvalidSelectorException;
021    import javax.jms.JMSException;
022    import org.apache.activemq.broker.Broker;
023    import org.apache.activemq.broker.ConnectionContext;
024    import org.apache.activemq.broker.region.group.MessageGroupMap;
025    import org.apache.activemq.command.ActiveMQMessage;
026    import org.apache.activemq.command.ConsumerInfo;
027    import org.apache.activemq.command.Message;
028    import org.apache.activemq.command.MessageAck;
029    import org.apache.activemq.usage.SystemUsage;
030    import org.slf4j.Logger;
031    import org.slf4j.LoggerFactory;
032    
033    public class QueueSubscription extends PrefetchSubscription implements LockOwner {
034    
035        private static final Logger LOG = LoggerFactory.getLogger(QueueSubscription.class);
036    
037        public QueueSubscription(Broker broker, SystemUsage usageManager, ConnectionContext context, ConsumerInfo info) throws InvalidSelectorException {
038            super(broker,usageManager, context, info);
039        }
040    
041        /**
042         * In the queue case, mark the node as dropped and then a gc cycle will
043         * remove it from the queue.
044         * 
045         * @throws IOException
046         */
047        protected void acknowledge(final ConnectionContext context, final MessageAck ack, final MessageReference n) throws IOException {
048            final Destination q = n.getRegionDestination();
049            final QueueMessageReference node = (QueueMessageReference)n;
050            final Queue queue = (Queue)q;
051            
052            if (n.isExpired()) {
053                // sync with message expiry processing
054                if (!broker.isExpired(n)) {
055                    LOG.warn("ignoring ack " + ack + ", for already expired message: " + n);
056                    return;
057                }
058            }
059            queue.removeMessage(context, this, node, ack);
060        }
061    
062        protected boolean canDispatch(MessageReference n) throws IOException {
063            boolean result = true;
064            QueueMessageReference node = (QueueMessageReference)n;
065            if (node.isAcked() || node.isDropped()) {
066                result = false;
067            }
068            result = result && (isBrowser() || node.lock(this));
069            return result;
070        }
071    
072        /**
073         * Assigns the message group to this subscription and set the flag on the
074         * message that it is the first message to be dispatched.
075         */
076        protected void assignGroupToMe(MessageGroupMap messageGroupOwners, MessageReference n, String groupId) throws IOException {
077            messageGroupOwners.put(groupId, info.getConsumerId());
078            Message message = n.getMessage();
079            if (message instanceof ActiveMQMessage) {
080                ActiveMQMessage activeMessage = (ActiveMQMessage)message;
081                try {
082                    activeMessage.setBooleanProperty("JMSXGroupFirstForConsumer", true, false);
083                } catch (JMSException e) {
084                    LOG.warn("Failed to set boolean header: " + e, e);
085                }
086            }
087        }
088    
089        public synchronized String toString() {
090            return "QueueSubscription:" + " consumer=" + info.getConsumerId() + ", destinations=" + destinations.size() + ", dispatched=" + dispatched.size() + ", delivered="
091                   + this.prefetchExtension + ", pending=" + getPendingQueueSize();
092        }
093    
094        public int getLockPriority() {
095            return info.getPriority();
096        }
097    
098        public boolean isLockExclusive() {
099            return info.isExclusive();
100        }
101    
102        /**
103         */
104        public void destroy() {
105            setSlowConsumer(false);
106        }
107    
108       
109        protected boolean isDropped(MessageReference node) {
110           boolean result = false;
111           if(node instanceof IndirectMessageReference) {
112               QueueMessageReference qmr = (QueueMessageReference) node;
113               result = qmr.isDropped();
114           }
115           return result;
116        }
117    
118    }