Enterprise JavaBeans 3.0, 5th Edition

Chapter WORKBOOK 8. Exercises for Chapter 10

This chapter focuses on exercises that illustrate the entity callback annotations and entity listener constructs discussed in Chapter 10 of the EJB book.

Exercise 10.1: Entity Callbacks

This exercise shows you a simple example of applying the entity callback annotations to an entity bean class. You will see the full life cycle of an entity bean as it is created, loaded, updated, and deleted. Of particular interest is when the Hibernate Entity Manager performs these callbacks. The example makes it clearer when Hibernate performs interactions with the database.

Start Up JBoss

If you already have JBoss running, there is no reason to restart it. Otherwise, start it up as instructed in Workbook 1.

Initialize the Database

The database tables will be created when Exercise 10.1 is deployed to JBoss. If you have problems running this example, shut down JBoss and run the clean.db Ant task.

Build and Deploy the Example Programs

Perform the following steps:

1. Open a command prompt or shell terminal and change to the ex10_1 directory created by the extraction process.

2. Set the JAVA_HOME and JBOSS_HOME environment variables to point to where your JDK and JBoss 4.0 are installed. Examples:

   Windows:

   C:\workbook\ex10_1> set JAVA_HOME=C:\jdk1.5.0
   C:\workbook\ex10_1> set JBOSS_HOME=C:\jboss-4.0.x

   Unix:

   $ export JAVA_HOME=/usr/local/jdk1.5.0
   $ export JBOSS_HOME=/usr/local/jboss-4.0

3. Add ant to your execution path. Ant is the build utility.

   Windows:

   C:\workbook\ex10_1> set PATH=..\ant\bin;%PATH% ...