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

MDB Example Revisited


We will go back to our earlier example and add in a few more features that we covered in the last few sections. To recap, we have a session bean, BankServiceBean, which sends a message to a JMS queue requesting that a new customer be added to the database. The message itself is a customer object. On receipt of the message, the MDB adds the customer to the database. This time we will use a topic instead of a queue.

In this example we will also assume that customers can be either high or low priority. To illustrate the message filtering capabilities of MDBs, the MDB we describe in this section will only process high priority customers. We can assume that a separate MDB will process low priority customers.

The only modification we make to BankServiceBean is to indicate that we are using a JMS topic and that we have a high priority customer. We do this using the ObjectMessage.setStringProperty() method. The MDB will subsequently filter out any low priority customers. The...