Professional BlazeDS: Creating Rich Internet Applications with Flex® and Java®

6.3. JMS

Java Message Service (JMS) is a standard API for messaging within a Java EE infrastructure. JMS is part of the Java EE specification. In this section, you will learn the fundamentals of JMS. For most readers, this section will be enough to get you ready to start using JMS with BlazeDS.

If you are already familiar with the subject, then you can rapidly browse through this section, just to review the underlying concepts, or even skip the section. On the other hand, if JMS is completely new to you, then you'll want to supplement the content in this section with the JMS tutorial that forms part of the Java EE tutorial, accessible at http://java.sun.com/j2ee/1.4/docs/tutorial/doc/ (for J2EE 1.4) and http://java.sun.com/javaee/5/docs/tutorial/doc/ (for Java EE 5). In addition, there are a lot of good books on JMS.

6.3.1. JMS Architecture

You learned about the two alternative messaging models, point-to-point and publish/subscribe, in the last section. JMS supports both those models. You also learned there that the messaging model is mostly asynchronous. With JMS, you can implement both synchronous and asynchronous behavior. For BlazeDS, though, we will continue to stick with asynchronous interactions.

The JMS API and infrastructure can be architecturally classified into three important parts:

• JMS provider — JMS provider implements the JMS API and provides a necessary infrastructure for creating, sending, receiving, and reading JMS messages.

• JMS clients — Programs that interact ...