Application-adapter communication

The adapter makes use of IBM's WebSphere MQ implementation of the Java Message Service (JMS). JMS is an open-standard API for accessing enterprise messaging systems. It is designed to allow business applications to asynchronously send and receive business data and events.

Message request

Figure 2 illustrates a message request communication. When the doVerbFor() method receives a business object from a collaboration, the adapter passes the business object to the data handler. The data handler converts the business object into XML text and the adapter issues it as a message to a queue. There, the JMS layer makes the appropriate calls to open a queue session and route the message.

Figure 2. Application-adapter communication method: Message request


Message return

Figure 3 illustrates the message return direction. The pollForEvents() method retrieves the next applicable message from the input queue. The message is staged in the in-progress queue where it remains until processing is complete. Using either the static or dynamic meta-objects, the adapter first determines whether the message type is supported. If so, the adapter passes the message to the configured data handler, which converts the message into a business object. The verb that is set reflects the conversion properties established for the message type. The adapter then determines whether the business object is subscribed to by a collaboration. If so, the gotApplEvents() method delivers the business object to InterChange Server, and the message is removed from the in-progress queue.

Figure 3. Application-adapter communication method: Message return


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