I'm trying to figure out the difference between a Durable Topic and a Queue in JMS.
At the surface, queues and topics differ in that a queue has 1 consumer but topics can have 0,1 or n consumers.
I think that's where the differences end - but not really in this case because a durable topic can have only one active subscriber at a time ( http://download.oracle.com/javaee/5/tutorial/doc/bncfu.html
To my understanding, messages in a queue are persisted until they are consumed. Same with a durable topic. For both, a Queue and Durable Topic the consuming process does not have to be running when messages are produced and the messages will be delivered when the consumer is brought up.