Generic JMS MDB Processing Questions

Question

Using MessageDrivenBean
This bean can only receive a message from the JMS queue server using its onMessage(Message msg) method. If onMessage is called and cannot process the message due to some external resource being down, it seems the only two outcomes are to wait for the external resource to be available, or queue the message to another queue. I've read throwing an exception is not a "good programming" practice. My questions are:
- Is the above the proper way to code the onMessage() method?
- Is there a way to shutdown the MessageDrivenBean or JMS queue server when exiting the application?
Thanks for your help.
Joe

Answer 1

Is it also possible to have the consumer close itself
by queuing a close message to the queue with highest
priority and the consumer calling its close()
method?Not if you using onMessage. A consumer is driven by a session, a session is singlethreaded and calls onMessage, a close must wait until all onMessage calls have been finsihed. Hence, if you call close within onMessage, you have a deadlock.
But you can use the synchronous receive() method of a consumer and call close after you've received it.
-- Andreas