TransientQueueSubscription xref

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    1   /***
    2    *
    3    * Copyright 2004 Protique Ltd
    4    *
    5    * Licensed under the Apache License, Version 2.0 (the "License");
    6    * you may not use this file except in compliance with the License.
    7    * You may obtain a copy of the License at
    8    *
    9    * http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   *
    17   **/
    18
    19  package org.codehaus.activemq.service.boundedvm;
    20  import java.util.List;
    21  import javax.jms.DeliveryMode;
    22  import javax.jms.JMSException;
    23  import org.codehaus.activemq.broker.BrokerClient;
    24  import org.codehaus.activemq.broker.BrokerConnector;
    25  import org.codehaus.activemq.filter.Filter;
    26  import org.codehaus.activemq.message.ActiveMQMessage;
    27  import org.codehaus.activemq.message.BrokerInfo;
    28  import org.codehaus.activemq.message.ConsumerInfo;
    29  import org.codehaus.activemq.message.Packet;
    30  import org.codehaus.activemq.message.util.MemoryBoundedQueue;
    31
    32  /***
    33   * A holder for Transient Queue consumer info and message routing
    34   *
    35   * @version $Revision: 1.6 $
    36   */
    37  public class TransientQueueSubscription extends TransientSubscription {
    38      private BrokerClient client;
    39      private String brokerName;
    40      private String clusterName;
    41      private MemoryBoundedQueue dispatchedQueue;
    42
    43      /***
    44       * Construct the TransientQueueSubscription
    45       *
    46       * @param client
    47       * @param dispatchedQueue
    48       * @param filter
    49       * @param info
    50       */
    51      public TransientQueueSubscription(BrokerClient client, MemoryBoundedQueue dispatchedQueue, Filter filter,
    52              ConsumerInfo info) {
    53          super(filter, info);
    54          this.client = client;
    55          this.dispatchedQueue = dispatchedQueue;
    56          if (client != null){
    57              BrokerConnector connector = client.getBrokerConnector();
    58              if (connector != null){
    59                  BrokerInfo bi = connector.getBrokerInfo();
    60                  if (bi != null){
    61                      this.brokerName = bi.getBrokerName();
    62                      this.clusterName = bi.getClusterName();
    63                  }
    64              }
    65          }
    66      }
    67
    68      /***
    69       * determines if the Subscription is interested in the message
    70       *
    71       * @param message
    72       * @return true if this Subscription will accept the message
    73       * @throws JMSException
    74       */
    75      public boolean isTarget(ActiveMQMessage message) throws JMSException {
    76          boolean result = false;
    77          if (message != null) {
    78              //make sure we don't loop messages around the cluster
    79              if (!client.isClusteredConnection() || !message.isEntryCluster(clusterName)
    80                      || message.isEntryBroker(brokerName)) {
    81                  result = filter.matches(message)
    82                          && (message.getJMSDeliveryMode() == DeliveryMode.NON_PERSISTENT || consumerInfo
    83                                  .getDestination().isTemporary());
    84              }
    85          }
    86          return result;
    87      }
    88
    89      /***
    90       * @return true if the consumer has capacity for more messages
    91       */
    92      public boolean canAcceptMessages() {
    93          return dispatchedQueue.size() <= consumerInfo.getPrefetchNumber();
    94      }
    95
    96      /***
    97       * Dispatch a message to the Consumer
    98       *
    99       * @param message
    100      * @throws JMSException
    101      */
    102     public void doDispatch(ActiveMQMessage message) throws JMSException {
    103         addDispatchedMessage(message);
    104         message = message.shallowCopy();
    105         message.setConsumerNos(new int[]{consumerInfo.getConsumerNo()});
    106         client.dispatch(message);
    107     }
    108
    109     /***
    110      * Add a dispatched message
    111      *
    112      * @param message
    113      */
    114     private void addDispatchedMessage(ActiveMQMessage message) {
    115         dispatchedQueue.enqueue(message);
    116     }
    117
    118     /***
    119      * Acknowledge the receipt of a message by a consumer
    120      *
    121      * @param id
    122      * @return the removed ActiveMQMessage with the associated id
    123      */
    124     public ActiveMQMessage acknowledgeMessage(String id) {
    125         ActiveMQMessage msg = (ActiveMQMessage) dispatchedQueue.remove(id);
    126         return msg;
    127     }
    128
    129     /***
    130      * @return all the unacknowledge messages
    131      */
    132     public List getUndeliveredMessages() {
    133         return dispatchedQueue.getContents();
    134     }
    135
    136     /***
    137      * close the subscription
    138      */
    139     public void close() {
    140         super.close();
    141         dispatchedQueue.close();
    142     }
    143 }