Professional Java for Web Applications

Chapter 18Using Messaging and Clustering for Flexibility and Reliability

IN THIS CHAPTER

• Deciding when to use messaging and clustering
• How to add messaging support to your application
• Distributing your messages across a cluster
• Using Advanced Message Queuing Protocol to distribute events

WROX.COM CODE DOWNLOADS FOR THIS CHAPTER

You can find the wrox.com code downloads for this chapter at http://www.wrox.com/go/projavaforwebapps on the Download Code tab. The code for this chapter is divided into the following major examples:

• Publish-Subscribe Project
• WebSocket-Messaging Project
• AMQP-Messaging Project

NEW MAVEN DEPENDENCIES FOR THIS CHAPTER

This chapter has no new Maven dependencies that you will use in future chapters. You’ll continue to use the Maven dependencies introduced in all previous chapters. You’ll use the following dependency only in the last section of this chapter and not in any other chapters.

        <dependency>
            <groupId>com.rabbitmq</groupId>
            <artifactId>amqp-client</artifactId>
            <version>3.2.3</version>
            <scope>compile</scope>
        </dependency>

RECOGNIZING WHEN YOU NEED MESSAGING AND CLUSTERING

Messaging and clustering are two critical features of enterprise applications. Interestingly, messaging and clustering capabilities can stand on their own and enhance your applications independently, but they can also work hand-in-hand to improve the flexibility, reliability, scalability, and availability of your applications. In this chapter you learn about what each topic ...