MQ Triggering

The queue manager defines certain conditions as constituting “trigger events”.

If triggering is enabled for a queue and a trigger event occurs, the queue manager sends a trigger message to a queue called an initiation queue. The presence of the trigger message on the initiation queue indicates that a trigger event has occurred.

1. Program A issues an MQPUT and puts a message into A-Q for Program B.

2. The queue manager processes this API call and puts the message into the  

  application queue.

3. It also finds out that the queue is triggered. It creates a trigger message and looks in the

  Process Definition to find the name of the application and puts it in the trigger message.

  The trigger message is put into the initiation queue.

4. The trigger monitor gets the trigger message from the initiation queue and starts the

   program specified.

5. The application program starts running and issues an MQGET to retrieve the message  from the application queue.

Process definition:

A process definition object defines an application that starts in response to a trigger event on a Web Sphere MQ queue manager.

Initiation queue:

Defining an initiation queue when a trigger event occurs, the queue manager puts a trigger message on the initiation queue specified in the application queue definition. Initiation queues have no special settings.