How to limit the number of MDB instances listening to a Jboss JMS queue

Question

I\'m having a problem with the following setup:

A Java application send email msg to a JMS queue, then an MDB listening to the queue get the email msg with the onMessage

Answer 1

Try an additional acitivation config property:

@ActivationConfigProperty( propertyName = "maxSession", propertyValue = "someNumber")

where someNumber is the maximum number of instances you want.

Answer 2

If JBoss 4 has an option to limit the instances of a stateless session bean, one option could be to move the message processing code to this bean, and pass the incoming JMS messages to it. (IIRC any failures in the bean would also cause the JMS message to be unacknowledged so it would retry automatically).