test

The Java EE 6 Tutorial

A Simple Example of Browsing Messages in a Queue

This section describes an example that creates a QueueBrowser object to examine messages on a queue, as described in JMS Queue Browsers. This section then explains how to compile, package, and run the example using the GlassFish Server.

Writing the Client for the Queue Browser Example

To create a QueueBrowser for a queue, you call the Session.createBrowser method with the queue as the argument. You obtain the messages in the queue as an Enumeration object. You can then iterate through the Enumeration object and display the contents of each message.

    The messagebrowser/src/java/MessageBrowser.java client performs the following steps:

  1. Injects resources for a connection factory and a queue.

  2. Creates a Connection and a Session.

  3. Creates a QueueBrowser:

    QueueBrowser browser = session.createBrowser(queue);

  4. Retrieves the Enumeration that contains the messages:

    Enumeration msgs = browser.getEnumeration();

  5. Verifies that the Enumeration contains messages, then displays the contents of the messages:

    if ( !msgs.hasMoreElements() ) { 
    System.out.println("No messages in queue");
} else { 
    while (msgs.hasMoreElements()) { 
        Message tempMsg = (Message)msgs.nextElement(); 
        System.out.println("Message: " + tempMsg); 
    }
}

  6. Closes the connection, which automatically closes the session and QueueBrowser.

The format in which the message contents appear is implementation-specific. In the GlassFish Server, the message format looks like this:


Message contents: 
Text:   This is message 3 from producer
Class:                  com.sun.messaging.jmq.jmsclient.TextMessageImpl
getJMSMessageID():      ID:14-129.148.71.199(f9:86:a2:d5:46:9b)-40814-1255980521747
getJMSTimestamp():      1129061034355
getJMSCorrelationID():  null
JMSReplyTo:             null
JMSDestination:         PhysicalQueue
getJMSDeliveryMode():   PERSISTENT
getJMSRedelivered():    false
getJMSType():           null
getJMSExpiration():     0
getJMSPriority():       4
Properties:             null

You will use the connection factory and queue you created in To Create JMS Administered Objects for the Synchronous Receive Example.

ProcedureTo Build, Package, Deploy, and Run the MessageBrowser Client Using NetBeans IDE

To build, package, deploy, and run the MessageBrowser example using NetBeans IDE, follow these steps.

You also need the Producer example to send the message to the queue, and one of the consumer clients to consume the messages after you inspect them. If you did not do so already, package these examples.

  1. In NetBeans IDE, select File->Open Project.

  2. In the Open Project dialog, navigate to:


    tut-install/examples/jms/simple/

  3. Select the messagebrowser folder.

  4. Select the Open as Main Project check box.

  5. Click Open Project.

  6. In the Projects tab, right-click the project and select Build.

  7. Run the Producer client, sending one message to the queue:

    1. Right-click the producer project and select Properties.

    2. Select Run from the Categories tree.

    3. In the Arguments field, type the following:


      queue

    4. Click OK.

    5. Right-click the project and select Run.

      The output of the client looks like this:


      Destination type is queue
Sending message: This is message 1 from producer

  8. Run the MessageBrowser client. Right-click the messagebrowser project and select Run.

    The output of the client looks like this:


    Message: 
Text: This is message 1 from producer
Class: com.sun.messaging.jmq.jmsclient.TextMessageImpl
getJMSMessageID(): ID:12-129.148.71.199(8c:34:4a:1a:1b:b8)-40883-1255980521747
getJMSTimestamp(): 1129062957611
getJMSCorrelationID(): null
JMSReplyTo: null
JMSDestination: PhysicalQueue
getJMSDeliveryMode(): PERSISTENT
getJMSRedelivered(): false
getJMSType(): null
getJMSExpiration(): 0
getJMSPriority(): 4
Properties: null
Message: 
Class: com.sun.messaging.jmq.jmsclient.MessageImpl
getJMSMessageID(): ID:13-129.148.71.199(8c:34:4a:1a:1b:b8)-40883-1255980521747
getJMSTimestamp(): 1129062957616
getJMSCorrelationID(): null
JMSReplyTo: null
JMSDestination: PhysicalQueue
getJMSDeliveryMode(): PERSISTENT
getJMSRedelivered(): false
getJMSType(): null
getJMSExpiration(): 0
getJMSPriority(): 4
Properties: null

    The first message is the TextMessage, and the second is the non-text control message.

  9. Run the SynchConsumer client to consume the messages.

    1. Right-click the synchconsumer project and select Properties.

    2. Select Run from the Categories tree.

    3. In the Arguments field, type the following:


      queue

    4. Click OK.

    5. Right-click the project and select Run.

      The output of the client looks like this:


      Destination type is queue
Reading message: This is message 1 from producer

ProcedureTo Build, Package, Deploy, and Run the MessageBrowser Client Using Ant and the appclient Command

To build, package, deploy, and run the MessageBrowser example using Ant, follow these steps.

You also need the Producer example to send the message to the queue, and one of the consumer clients to consume the messages after you inspect them. If you did not do so already, package these examples.

To run the clients, you need two terminal windows.

  1. In a terminal window, go to the messagebrowser directory.


    cd ../messagebrowser

  2. Type the following command:


    ant

    The targets place the application client JAR file in the dist directory for the example.

  3. Go to the producer directory.

  4. Run the Producer client, sending one message to the queue:


    appclient -client client-jar/producerClient.jar queue

    The output of the client looks like this (along with some application client container output):


    Destination type is queue
Sending message: This is message 1 from producer

  5. Go to the messagebrowser directory.

  6. Deploy the client JAR file to the GlassFish Server, then retrieve the client stubs:


    ant getclient

    Ignore the message that states that the application is deployed at a URL.

  7. Because this example takes no command-line arguments, you can run the MessageBrowser client using the following command:


    ant run

    Alternatively, you can type the following command:


    appclient -client client-jar/messagebrowserClient.jar

    The output of the client looks like this (along with some application client container output):


    Message: 
Text: This is message 1 from producer
Class: com.sun.messaging.jmq.jmsclient.TextMessageImpl
getJMSMessageID(): ID:12-129.148.71.199(8c:34:4a:1a:1b:b8)-40883-1255980521747
getJMSTimestamp(): 1255980521747
getJMSCorrelationID(): null
JMSReplyTo: null
JMSDestination: PhysicalQueue
getJMSDeliveryMode(): PERSISTENT
getJMSRedelivered(): false
getJMSType(): null
getJMSExpiration(): 0
getJMSPriority(): 4
Properties: null
Message: 
Class: com.sun.messaging.jmq.jmsclient.MessageImpl
getJMSMessageID(): ID:13-129.148.71.199(8c:34:4a:1a:1b:b8)-40883-1255980521767
getJMSTimestamp(): 1255980521767
getJMSCorrelationID(): null
JMSReplyTo: null
JMSDestination: PhysicalQueue
getJMSDeliveryMode(): PERSISTENT
getJMSRedelivered(): false
getJMSType(): null
getJMSExpiration(): 0
getJMSPriority(): 4
Properties: null

    The first message is the TextMessage, and the second is the non-text control message.

  8. Go to the synchconsumer directory.

  9. Run the SynchConsumer client to consume the messages:


    appclient -client client-jar/synchconsumerClient.jar queue

    The output of the client looks like this (along with some application client container output):


    Destination type is queue
Reading message: This is message 1 from producer