MQSeries.net :: View topic - Strange problem with JMS messages and broker

aks · Posted: Wed Jul 14, 2004 7:34 am Post subject:

I have raised a PMR with IBM on the following problem, but they are yet to shed any light on it.

For the PMR, I have a flow which accepts an XML message on an MQInput node, transforms it to COBOL copybook format with an XMLTransformation node which is then connected to an MQOutput node. For even more simplicity, I have now just wired the MQOutput node to the MQInput. The message is put on the queue with a Java program that uses the MQI base classes. Every time I run the program (from a Windows XP command line), the message is put on the input queue and flowed to the output queue, without any problem.

When I change my program to use the JMS classes, I run the prgram, the first message is put on the inut queue and is flowed to the output queue. However, the 2nd and subsequent times I run the program, the broker does not read the messages and the messages just stay on the input queue.

The service trace I provided to IBM shows that the first time, an MQGET is issued and the message is processed by the broker. The 2nd time, just 2033 (message not available) entries are logged.

I can't explain why. The JMS java app does the following steps:
1) QueueConnection opened
2) QueueSession opened
3) QueueSender opend
4) jaxax.jms.Message sent
5) QueueSender closed
6) QueueSession committed
7) QueueSession closed
8 QueueConnection stopped
9) QueueConnection closed

The messages are put on the queue every time, but the broker only reads the first. I have to stop and restart the broker to get the first message to be read, then the problem happens again

Does any one know why this would happen? Is it possible that even though the Java app finishes normally, the queue is locked for read for some reason?

Thanks
Alan