We had a rather unique situation some time ago where our message broker log was recording the JMSException for an Invalid acknowledgement.
We traced it to the fact that the consumer of the message was using a more recent version of ActiveMQ than our message broker was running (i.e. message broker was v5.5.1 and the consumer was >v5.5.1). We would like to recreate this error in one of our test environments so that we can learn more about it. It appears that the exception was related to a consumer acknowledging a message. We determined this from observing that the specific exception that was thrown appears to originate in only one place, that is the acknowledge() function of the TopicSubscription class. I have configured an environment with a v5.5.1 message broker and a consumer and producer compiled with v5.11.0 of ActiveMQ. The producer sends messages to a topic and the consumer receives these messages and then acknowledges those messages. The session was configured for client acknowledgement. Under these conditions I could not reproduce the exception described above. I tried looking through the source code for the acknowledge() function of the ActiveMQMessage class to see if I could determine how my consumer call to acknowkedge() landed on the TopicSubscription acknowledge(), but have been unable to make a connection between the acknowledge() function in ActiveMQMessage and TopicSubscription even after following the calls starting with the call to ActiveMQMessage acknowledge(). Can you offer any explanation as to why I am unable to trace the functions calls to TopicSubscription acknowledge? And more importantly, can you offer any advice on how I might recreate the exception condition described here? Thanks, Mike Michael Tarullo Contractor (Engility Corp) Software Engineer FAA WJH Technical Center (609)485-5294
