Publish/Subscribe Client Acknowledgements!?

Question

Hi all.
Im experimenting with the simplePublishSubscribe example from sun's JMS tutorial, trying to understand how the acknowledgements work when in CLIENT_ACKNOWLEDGEMENT mode.
So I set the above mode for the session and run the example without any message.acknowledgment() 's. So now after the the publish message have been delivered to the subscriber, without being acknowledged from the client, running topicSession.recover() should result in all the previous messages being redelivered to the client as they have not been acknowledged and therefore not deleted from the topic.
However after trying this it would seem that not messages are redelivered to the client!? Any advice on this scenario. It is important since the application we are designing relies on client acknowledgements in an asyncronous mode.
Thanks
(PS...i have search the forum and nnot found a definitive answer to this problem)

Answer 1

Hi,
The following code should work as you expect:
session = connection.createTopicSession(false,Session.CLIENT_ACKNOWLEDGE);
subscriber = session.createSubscriber( topic );
message = subscriber.receive();
mID = message.getJMSMessageID();
session.recover();
message = subscriber.receive();
newMID = message.getJMSMessageID();
if( ! mID.equals( newMID ) )
     //fail!!!
Arnaud
http://www.arjuna.com