Thank you Tim. Michael Tarullo Contractor (Engility Corp) Software Engineer FAA WJH Technical Center (609)485-5294
-----Original Message----- From: tbai...@gmail.com [mailto:tbai...@gmail.com] On Behalf Of Tim Bain Sent: Thursday, September 01, 2016 8:47 AM To: ActiveMQ Users Subject: Re: Need Help With A JMS Exception Since you have the 5.5.1 source code, I recommend you attach a debugger to the broker process and set a breakpoint on the TopicSubscription.acknowledge() method; the stack will tell you how you got there. Setting breakpoints on the broker can lead to instability and may force you to restart it (plus you have to restart it to enable the debug port and again to disable it, and it's a security vulnerability while it's open), so do this in a dev/test environment, not a production one. You should not expect that there would be a call chain between the two methods you referenced. One is executed on the client and one is executed on the broker, so between the two there is the creation, transmission, and handling of the acknowledgement message. Tim On Aug 31, 2016 4:15 PM, <michael.ctr.taru...@faa.gov> wrote: > 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 > >
