Supporting application programs that use the MQI

WebSphere MQ application programs need certain objects before they can run successfully. For example, Figure 1 shows an application that removes messages from a queue, processes them, and then sends some results to another queue on the same queue manager.

Figure 1. Queues, messages, and applications

Whereas applications can put messages onto local or remote queues (using MQPUT), they can only get messages directly from local queues (using MQGET).

Before this application can run, the following conditions must be satisfied:

• The queue manager must exist and be running.
• The first application queue, from which the messages are to be removed, must be defined.
• The second queue, on which the application puts the messages, must also be defined.
• The application must be able to connect to the queue manager. To do this it must be linked to WebSphere MQ. See the WebSphere MQ Application Programming Guide for more information.
• The applications that put the messages on the first queue must also connect to a queue manager. If they are remote, they must also be set up with transmission queues and channels. This part of the system is not shown in Figure 1.