The JMS 1.1 model

 

We can write a JMS application using two styles of messaging:

• Point-to-point

• Publish/subscribe

These styles of messaging are also referred to as messaging domains and we can combine both styles of messaging in one application.

With versions of JMS before JMS 1.1, programming for the point-to-point domain uses one set of interfaces and methods, and programming for the publish/subscribe domain uses another set. The two sets are similar, but separate. With JMS 1.1, we can use a common set of interfaces and methods that support both messaging domains. The common interfaces provide a domain independent view of each messaging domain. Table 1 lists the JMS 1.1 domain independent interfaces and their corresponding domain specific interfaces.

The JMS 1.1 domain independent interfaces

Domain independent interfaces	Domain specific interfaces for the point-to-point domain	Domain specific interfaces for the publish/subscribe domain
ConnectionFactory	QueueConnectionFactory	TopicConnectionFactory
Connection	QueueConnection	TopicConnection
Destination	Queue	Topic
Session	QueueSession	TopicSession
MessageProducer	QueueSender	TopicPublisher
MessageConsumer	QueueReceiver QueueBrowser	TopicSubscriber

JMS 1.1 retains all the domain specific interfaces in JMS 1.0.2b, and so existing applications can still use these interfaces. For new applications, however, consider using the JMS 1.1 domain independent interfaces.

In the WebSphere MQ JMS implementation of JMS 1.1, the administered objects are the following:

• ConnectionFactory

• Queue

• Topic

Destination is an abstract superclass of Queue and Topic, and so an instance of Destination is either a Queue or a Topic object. The domain independent interfaces treat a queue or a topic as a destination. The messaging domain for a MessageConsumer or a MessageProducer object is determined by whether the destination is a queue or a topic.

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