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Passing data to/from the mainframe

I'm working on an unemployment reporting system for the state of Missouri. We are using WebSphere and MQ to pass data from/to the mainframe COBOL/CICS system and the JAVA front-end system.

We have successfully been able to pass data through the COMMAREA and have it written and read to MQ queues. We need to be able to update the queue with multiple messages from one program so we need to be able to directly put data into the queue not just update the queue from COMMAREA data being passed to the CICS bridge.

We cannot connect, open or put data to the queue. We abend every time we try. Can you give us any help, suggestions, places to look, debugging ideas, etc.?

I think I'd recommend a bit of a tweak in your design to accomplish what you need. The bridge functions are really designed for one-in and one-out operation. What you want is a one-in and lots-out arrangement.

The MQ facilities within CICS rely on the fact that there is only one QM concerned and one input mechanism (the trigger queue) to get things going. I suggest that you amend your Java application that does the MQ PUT into a QUEUE that is destined to be read by CICS to start a new (non-Bridge) transaction that you will write.

The arrival of a message in the trigger queue scanned by CICS will get the (new) requested transaction going and you have access to the contents of the trigger via the Startdata. Thus, you know the queue from which to obtain the sent message and the ReplyToQ to be used for the results. Thus, you can put as many messages as you want into this ReplytoQ and from as many places as the name of this ReplyToQ is known.

I'd just be a little thoughtful about the UnitOfWork considerations if you are using lots of CICS transactions to generate the replies and I'd certainly write the Java-receiving application not to be dependant on the order of items in the ReplyToQ (i.e. use information in the message header to determine relative placement).

Robert Harris
CICS Technical Strategist -- CICS expert at Search390.com

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