Book Image

EJB 3 Developer Guide

By : Michael Sikora
Book Image

EJB 3 Developer Guide

By: Michael Sikora

Overview of this book

Table of Contents (18 chapters)
EJB 3 Developer Guide
Credits
About the Author
About the Reviewers
Preface
Annotations and Their Corresponding Packages

Chapter 8. Messaging

In this chapter we discuss the Java Message Service API before moving on to Message-driven beans. In particular we will cover:

  • Java Message Service (JMS) API

  • Point-to-point and publish/subscribe messaging models

  • Queue producer and consumer examples

  • Topic producer and consumer examples

  • Message-driven beans (MDBs)

  • MDB activation configuration properties

  • MDB lifeCycle

  • Sending message confirmation to a client

  • MDBs and transactions

Introduction

So far our examples have all been synchronous. For example, a client invokes a session bean which performs some operation while the client waits. When the session bean completes its operation (or operations), control is passed back to the client and the client continues with the remaining operations. For some applications an asynchronous mode of operation is more appropriate, particularly in business to business applications. For example, a client may send a message requesting that an order be processed. The order processing may take some time...