Enterprise JavaBeans, Fourth Edition

Chapter 30. Exercises for Chapter 13

Exercise 13.1: EJB Timer Service

In this exercise, you will learn how to use work with the EJB Timer Service. The examples in this chapter match the modifications made to the Ship EJB to enable Timers. This exercise builds off the code within Exercise 12.1, so initialization and deployment should be around the same.

Clean the Database

You need to clean and refresh the database. To do this, shutdown JBoss if you have it running and run ant clean.db. Then restart JBoss.

Build and Deploy Example Programs

Perform the following steps:

1. Open a command prompt or shell terminal and change to the ex13_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\ex13_1> set JAVA_HOME=C:\jdk1.4.2 C:\workbook\ex13_1> set JBOSS_HOME=C:\jboss-4.0

   Unix:$ export JAVA_HOME=/usr/local/jdk1.4.2 $ export JBOSS_HOME=/usr/local/jboss-4.0

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

   Windows:C:\workbook\ex13_1> set PATH=..\ant\bin;%PATH%

   Unix:$ export PATH=../ant/bin:$PATH

4. The exercise uses a JMS Topic. Deploy the topic using the following Ant target.

   $ ant make-topic

5. Build the EJBs used in this example.

   $ ant

   You will see titan.jar copied to the JBoss deploy directory and redeployed by the application server.

6. Initialize the database.You will see a bunch of entity beans being created.

$ ant createdb

Examine the Service Code

The scheduleMaintenance, ...