Publish / Subscribe is one of several messaging paradigms available in Universal Messaging. Universal Messaging Channels are a logical rendezvous point for publishers (producers) and subscribers (consumers) or data (events).
Universal Messaging DataStreams and DataGroups provide an alternative style of Publish/Subscribe where user subscriptions can be managed remotely on behalf of clients (see
Publish / Subscribe Using DataStreams and DataGroups).
Universal Messaging Channels equate to Topics if you are using the Universal Messaging Provider for JMS.
Under the publish / subscribe paradigm, each event is delivered to each subscriber once and only once per subscription, and is not typically removed from the channel as a result of the message being consumed by an individual client.
This section demonstrates how Universal Messaging pub / sub works in Java, and provides example code snippets for all relevant concepts:
Creating a Universal Messaging Channel