Hi, In our application, we have a dozen JMS queues and corresponding MDBs, running against an external ActiveMQ server. All this is running reliably.
Recently, we had to add a new queue with the following requirement: Some messages should not get processed concurrently. It looked like ActiveMQ Message Groups is built for this purpose so we added JMSXGroupID to messages that shouldn’t get processed concurrently (Reference: http://activemq.apache.org/message-groups.html <http://activemq.apache.org/message-groups.html>) However, this has not worked as we expected: Even though the container is using a single MessageConsumer (which may be respecting our JMSXGroupID settings), the onMessage method of multiple MDB instances are getting called concurrently for the same JMSXGroupID — and that is not acceptable per our requirement. Is there a way around this using MDBs? E.g. some kind of TomEE or ActiveMQ setting? If this is not possible using MDBs, what kind of architecture can be used to solve this problem? (We thought about creating our own MessageConsumer in a Singleton and have it continuously poll this new queue but we are not excited about it. This would not scale well and we don’t like the idea to manage transactions on our own. Another idea we had was to use ReentrantLocks, but we realized that we have to release the lock after transaction is completed and we don’t have access to that from a stateless session bean. That solution is messy in other fronts as well so again, we are not excited about it). Any help will be greatly appreciated. Thanks, Ihsan.
