Chapter 2. Developing a Simple Example
Now that you understand Message-Oriented Middleware and some JMS concepts, you are ready to write your first JMS application. Although it would be easier to demonstrate a simple example using the more widely used point-to-point model, the publish-and-subscribe model offers a more interesting example. Therefore, in this chapter we will provide a gentle introduction to JMS using the publish-and-subscribe messaging model. You will get your feet wet with JMS and learn some of the basic classes and interfaces. Chapter 4 covers the point-to-point model in detail using a real-world example, and Chapter 5 covers the publish-and-subscribe messaging model following up on the same example.
As with all examples in this book, example code and instructions specific to several vendors are available for download on O’Reilly’s website at http://oreilly.com/catalog/9780596522049/examples. You will need to install and configure your JMS provider according to the instructions provided by your vendor. To illustrate a sample vendor configuration, we will be using ActiveMQ version 5.2, a popular robust and production-quality open source JMS provider (see http://activemq.apache.org). You can find the basic installation instructions and configuration settings for executing the code examples in this book in Appendix D.
The Chat Application
Internet chat provides an interesting application for learning about the JMS pub/sub messaging model. Used mostly for entertainment, ...