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.apache.commons.logging.Log;
031    import org.apache.commons.logging.LogFactory;
032    
033    public class QueueSubscription extends PrefetchSubscription implements LockOwner {
034    
035        private static final Log LOG = LogFactory.getLog(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                if (broker.isExpired(n)) {
054                    queue.messageExpired(context, this, node);
055                } else {
056                    LOG.debug("ignoring ack " + ack + ", for already expired message: " + n);
057                }
058                return;
059            }
060            queue.removeMessage(context, this, node, ack);
061        }
062    
063        protected boolean canDispatch(MessageReference n) throws IOException {
064            boolean result = true;
065            QueueMessageReference node = (QueueMessageReference)n;
066            if (node.isAcked() || node.isDropped()) {
067                result = false;
068            }
069            result = result && (isBrowser() || node.lock(this));
070            return result;
071        }
072    
073        /**
074         * Assigns the message group to this subscription and set the flag on the
075         * message that it is the first message to be dispatched.
076         */
077        protected void assignGroupToMe(MessageGroupMap messageGroupOwners, MessageReference n, String groupId) throws IOException {
078            messageGroupOwners.put(groupId, info.getConsumerId());
079            Message message = n.getMessage();
080            if (message instanceof ActiveMQMessage) {
081                ActiveMQMessage activeMessage = (ActiveMQMessage)message;
082                try {
083                    activeMessage.setBooleanProperty("JMSXGroupFirstForConsumer", true, false);
084                } catch (JMSException e) {
085                    LOG.warn("Failed to set boolean header: " + e, e);
086                }
087            }
088        }
089    
090        public synchronized String toString() {
091            return "QueueSubscription:" + " consumer=" + info.getConsumerId() + ", destinations=" + destinations.size() + ", dispatched=" + dispatched.size() + ", delivered="
092                   + this.prefetchExtension + ", pending=" + getPendingQueueSize();
093        }
094    
095        public int getLockPriority() {
096            return info.getPriority();
097        }
098    
099        public boolean isLockExclusive() {
100            return info.isExclusive();
101        }
102    
103        /**
104         */
105        public void destroy() {
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    }