Java Enterprise in a Nutshell, Second Edition

Elements of Messaging with JMS

The principle players in a JMS system are messaging clients , message destinations , and a JMS-compatible messaging provider .

Messaging clients produce and consume messages. Typically messaging takes place asynchronously; a client produces a message and sends it to a message destination, and some time later another client receives the message. Message clients can be implemented using JMS, or they can use a native messaging API to participate in the messaging system. If a native message client (e.g., a client using the native IBM MQ Series APIs) produces a message to a message destination, a JMS connection to the native message system is responsible for retrieving the message, converting it into the appropriate JMS message representation, and delivering it to any relevant JMS-based clients.

Message destinations are places where JMS clients send and receive messages from. Message destinations are created within a JMS provider that manages all of the administrative and runtime functions of the messaging system. At a minimum, a JMS provider allows you to specify a network address for a destination, allowing clients to find the destination on the network. But providers may also support other administrative options on destinations, such as persistence options, resource limits, etc.

Messaging Styles: Point-to-Point and Publish-Subscribe

Generally speaking, asynchronous messaging usually comes in two flavors: a message can be addressed and sent to a single ...