Enterprise JavaBeans 3.0, 5th Edition

Chapter WORKBOOK 4. Exercises for Chapter 6

Chapter 6 of the EJB book walked you through some basic object-to-relational mappings for the persistent properties of your entity bean classes. The exercises in this chapter use a lot of the example code from Chapter 6 to illustrate basic mapping types. You will see examples of:

• Autogenerated primary keys

• @IdClass and @EmbeddedId primary key class mappings

• @Temporal, @Transient, @Lob , and @Enumerated mappings

• An entity class that maps to multiple tables

• An entity class that has an embedded class as a property

Exercise 6.1: Basic Property Mappings

This exercise shows you an example of the @Temporal, @Lob, and @Enumerated mapping types discussed in Chapter 6, as well as an example of an autogenerated primary key.

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 6.1 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 ex06_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\ex06_1> set JAVA_HOME=C:\jdk1.5.0
   C:\workbook\ex06_1> set JBOSS_HOME=C:\jboss-4.0.x

   Unix:

   $ export JAVA_HOME=/usr/local/jdk1.5.0 ...