SimpleQueueReceiver xref

    1   /*
    2    *
    3    * Copyright 2002 Sun Microsystems, Inc. All Rights Reserved.
    4    *
    5    * Redistribution and use in source and binary forms, with or
    6    * without modification, are permitted provided that the following
    7    * conditions are met:
    8    *
    9    * - Redistributions of source code must retain the above copyright
    10   *   notice, this list of conditions and the following disclaimer.
    11   *
    12   * - Redistribution in binary form must reproduce the above
    13   *   copyright notice, this list of conditions and the following
    14   *   disclaimer in the documentation and/or other materials
    15   *   provided with the distribution.
    16   *
    17   * Neither the name of Sun Microsystems, Inc. or the names of
    18   * contributors may be used to endorse or promote products derived
    19   * from this software without specific prior written permission.
    20   *
    21   * This software is provided "AS IS," without a warranty of any
    22   * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
    23   * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
    24   * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
    25   * EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY
    26   * DAMAGES OR LIABILITIES SUFFERED BY LICENSEE AS A RESULT OF OR
    27   * RELATING TO USE, MODIFICATION OR DISTRIBUTION OF THIS SOFTWARE OR
    28   * ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE
    29   * FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT,
    30   * SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER
    31   * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF
    32   * THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS
    33   * BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
    34   *
    35   * You acknowledge that this software is not designed, licensed or
    36   * intended for use in the design, construction, operation or
    37   * maintenance of any nuclear facility.
    38   *
    39   */
    40  /***
    41   * The SimpleQueueReceiver class consists only of a main method,
    42   * which fetches one or more messages from a queue using
    43   * synchronous message delivery.  Run this program in conjunction
    44   * with SimpleQueueSender.  Specify a queue name on the command
    45   * line when you run the program.
    46   */
    47  package org.codehaus.activemq.demo;
    48
    49  import javax.jms.JMSException;
    50  import javax.jms.Message;
    51  import javax.jms.Queue;
    52  import javax.jms.QueueConnection;
    53  import javax.jms.QueueConnectionFactory;
    54  import javax.jms.QueueReceiver;
    55  import javax.jms.QueueSession;
    56  import javax.jms.Session;
    57  import javax.jms.TextMessage;
    58  import javax.naming.Context;
    59  import javax.naming.InitialContext;
    60  import javax.naming.NamingException;
    61
    62  public class SimpleQueueReceiver {
    63
    64      /***
    65       * Main method.
    66       *
    67       * @param args the queue used by the example
    68       */
    69      public static void main(String[] args) {
    70          String queueName = null;
    71          Context jndiContext = null;
    72          QueueConnectionFactory queueConnectionFactory = null;
    73          QueueConnection queueConnection = null;
    74          QueueSession queueSession = null;
    75          Queue queue = null;
    76          QueueReceiver queueReceiver = null;
    77          TextMessage message = null;
    78
    79          /*
    80           * Read queue name from command line and display it.
    81           */
    82          if (args.length != 1) {
    83              System.out.println("Usage: java " +
    84                      "SimpleQueueReceiver <queue-name>");
    85              System.exit(1);
    86          }
    87          queueName = new String(args[0]);
    88          System.out.println("Queue name is " + queueName);
    89
    90          /*
    91           * Create a JNDI API InitialContext object if none exists
    92           * yet.
    93           */
    94          try {
    95              jndiContext = new InitialContext();
    96          }
    97          catch (NamingException e) {
    98              System.out.println("Could not create JNDI API " +
    99                      "context: " + e.toString());
    100             System.exit(1);
    101         }
    102
    103         /*
    104          * Look up connection factory and queue.  If either does
    105          * not exist, exit.
    106          */
    107         try {
    108             queueConnectionFactory = (QueueConnectionFactory)
    109                     jndiContext.lookup("QueueConnectionFactory");
    110             queue = (Queue) jndiContext.lookup(queueName);
    111         }
    112         catch (NamingException e) {
    113             System.out.println("JNDI API lookup failed: " +
    114                     e.toString());
    115             System.exit(1);
    116         }
    117
    118         /*
    119          * Create connection.
    120          * Create session from connection; false means session is
    121          * not transacted.
    122          * Create receiver, then start message delivery.
    123          * Receive all text messages from queue until
    124          * a non-text message is received indicating end of
    125          * message stream.
    126          * Close connection.
    127          */
    128         try {
    129             queueConnection =
    130                     queueConnectionFactory.createQueueConnection();
    131             queueSession =
    132                     queueConnection.createQueueSession(false,
    133                             Session.AUTO_ACKNOWLEDGE);
    134             queueReceiver = queueSession.createReceiver(queue);
    135             queueConnection.start();
    136             while (true) {
    137                 Message m = queueReceiver.receive(1);
    138                 if (m != null) {
    139                     if (m instanceof TextMessage) {
    140                         message = (TextMessage) m;
    141                         System.out.println("Reading message: " +
    142                                 message.getText());
    143                     }
    144                     else {
    145                         break;
    146                     }
    147                 }
    148             }
    149         }
    150         catch (JMSException e) {
    151             System.out.println("Exception occurred: " +
    152                     e.toString());
    153         }
    154         finally {
    155             if (queueConnection != null) {
    156                 try {
    157                     queueConnection.close();
    158                 }
    159                 catch (JMSException e) {
    160                 }
    161             }
    162         }
    163     }
    164 }