Monitoring Sun Java^TM System Message Queue

Enterprise Manager enables you to manage Sun Java^TM System Message Queue. You can perform the following tasks:

• Monitor topics and queues

• Send and publish messages

• View message properties

• View and edit message payload

Enterprise Manager provides a unified management environment for Sun JMS IQ Manager, Sun Java System Message Queue, and Sun Java Message Service Grid (JMS Grid). However, the level of monitoring and management capabilities supported vary for the different message servers.

For basic information about Enterprise Manager, see Enterprise Manager Basics.

A topic conforms to the publish-and-subscribe (pub/sub) messaging domain, where one publisher broadcasts messages to potentially many subscribers. When the message server publishes a message on a topic, it ensures that all subscribers receive the message.

A queue conforms to the point-to-point (p2p, or PTP) messaging domain, where one sender delivers a message to exactly one receiver. When the message server sends a message to a queue, it ensures that the message is received once and only once, even though there might be many receivers “listening” to the queue. This is equivalent to the subscriber pooling in other queue implementations.

Except for this distinction between pub/sub and PTP, topics and queues are quite similar.

• Each topic or queue maintains a sequence of messages in progress.

• Each message has a timestamp called the enqueue time, which indicates when the message was published or sent.

• Messages that have been read and committed by their subscribers or receivers are subject to cleanup. After cleanup, the lowest sequence number is increased by the number of messages that were delivered and successfully committed.

Monitoring Topics and Queues

You can use Enterprise Manager to monitor message traffic in topics and queues.

To Monitor Topics and Queues

1. In the Explorer panel of Enterprise Manager, select the Sun Java System Message Queue node (for example, Sun_JMQ_7676).

   The following table describes the columns that appear for a topic.

   Column Name	Description
   Topic Name	The name of the topic.
   Min Sequence Number	This column is not applicable to Sun Java System Message Queue.
   Max Sequence Number	This column is not applicable to Sun Java System Message Queue.
   Available Count	The number of messages for this topic that are still unprocessed by at least one subscriber.
   Number of Subscribers	The number of subscribers registered to consume messages for this topic (including durable subscribers that are currently disconnected).
   Last Published Date/Time	This column is not applicable to Sun Java System Message Queue.

   The following table describes the columns that appear for a queue.

   Column Name	Description
   Queue Name	The name of the queue.
   Min Sequence Number	This column is not applicable to Sun Java System Message Queue.
   Max Sequence Number	This column is not applicable to Sun Java System Message Queue.
   Available Count	The number of unprocessed messages in the queue.
   Number of Receivers	The number of receivers for this queue.
   Last Published Date/Time	This column is not applicable to Sun Java System Message Queue.

2. The Messages tab in the lower portion of the Details panel displays information about any messages in the topic or queue. The Messages tab includes a toolbar.

3. Topics also include a Summary tab and a Subscribers tab. The Subscribers tab displays information about durable subscribers. The toolbar enables you to create a new durable subscriber and to unsubscribe an existing durable subscriber.

Sending and Publishing Messages

You can send and publish messages from Enterprise Manager. The messages can be text or binary.

To Send and Publish Messages

1. Select the topic or queue as described in Monitoring Topics and Queues.

2. In the Messages tab, click the Send/Publish icon.

   The Send/Publish New Message dialog box appears.

3. If you want to publish a text message, then select the Text option and enter the text or specify the text file.

4. If you want to publish a binary message, then select the Binary option and specify the binary file.

5. Review the default values for the Time to Live, Priority, and Delivery Mode fields. If desired, change the default values.

   The Time to Live field has a default value of 0, which specifies that the message does not expire.

6. Click Submit.

Viewing Message Properties

You can view the properties of a message. The properties include the message type, destination name, and expiration time.

To View Message Properties

1. Select the topic or queue as described in Monitoring Topics and Queues.

2. In the Messages tab, select the message and click the Properties icon.

   The View Message Property dialog box appears. The following table describes the message properties.

   Property Name	Description
   Correlation ID	An identifier that is used to associate the message with a previous message or application-specific identifier. The default internal value is Sun-SeeBeyond.
   Time Stamp	The date and time when the message was received.
   Message Payload Size	This property is not applicable to Sun Java System Message Queue.
   Message Source File	This property is not applicable to Sun Java System Message Queue.
   Type	The message type of the message, such as text or bytes.
   Message Enqueue Time	The date and time when the message was received by its message destination.
   Delivery Mode	Indicates whether the message is persistent or nonpersistent.
   Message Size	This property is not applicable to Sun Java System Message Queue.
   Sequence Number	The sequence number of the message.
   Redelivery Flag	Indicates whether this message is set for redelivery.
   Destination Name	The name of the topic or queue.
   Message ID	The unique identification number for the message.
   Priority	The priority of the message from 0 to 9. The lowest priority is 0. The highest priority is 9.
   Expiration Time	The date and time when the message will expire.

3. When you are done, click Close.

Viewing and Editing Message Payload

A message contains two main components: the headers and the payload. The headers contain metadata about the message. The payload contains the actual content of the message.

Text Messages

Enterprise Manager enables you to view and edit the payload of live text messages.

To View and Edit the Payload of Live Text Messages

1. Select the topic or queue as described in Monitoring Topics and Queues.

2. In the Messages tab, select the message and click the View/Edit icon.

   The Text Message Payload (Live) dialog box appears.

3. To display any carriage return and line feed characters in the message, select the Show Carriage Return/Line Feed check box.

4. If the message contains XML and you want to view the XML in browser format, click View XML.

5. To change the payload, do one of the following:

   • Modify the text in the text area and click Change Payload.

   • Select the From File option, select the text file, and click Change Payload.

6. To delete the message, click Delete.

7. To save the payload to a file, click Download Payload.

Byte Messages

Enterprise Manager enables you to view the payload of live byte messages. You cannot edit the payload.

To View the Payload of Live Byte Messages

1. Select the topic or queue as described in Monitoring Topics and Queues.

2. In the Messages tab, select the message and click the View/Edit icon.

   The Bytes Message Payload (Live) dialog box appears.

3. To delete the message, click Delete.

4. To save the payload to a file, click Download Payload.