Getting Started with WebSphere Application Server

Chapter 5 – Enterprise Java Beans 99
In this step, a JPA project is created with eclipse. The JPA project often contains several
entities generated from the database. To make use of the JPA entities, other projects
such as Web projects, and EJB projects often depend on JPA projects. The referenced
JPA project will be deployed with the Web project or EJB project together in Community
Edition.
3. Create a database connection in Eclipse
Since the database pool has been created in the Community Edition server, a
connection is needed in Eclipse. With this database connection, the data management
plug-in can get database information to prepare for the generation of JPA entities.
4. Generate JPA entities
JPA can map Java classes to database entities. Once the tables in the database have
been defined, several JPA entities can be generated directly from these tables. In that
way, both EJB project and Web project can make use of the generated entities.
An example using JPAs is provided in the Exercises section of this chapter.
5.5 Summary
This chapter discussed EJB 3.0 related topics with Community Edition, including EJB 3.0
development, application client development and JPA entities application in Community
Edition.
5.6 Exercises
In this exercise you will develop an EJB, JPA and a servlet to calculate university credits of
students. You will use Eclipse with the WEP installed and DB2 Express-C 9.7. Credits of all
the students will be shown using a servlet.
Note:
The exercise complete code and solutions are provided in the zip file
gettingStartedWithWasceEdition1st_src.zip accompanying this book.
Follow these steps:
1. Create a database and a table in DB2 Express-C 9.7
Follow the steps introduced in Chapter 4.2.1 – Creating a database, to create a
database called Studntdb as shown in Figure 5.3.