Special Edition Using Enterprise JavaBeans™ 2.0

Building Portable Entity Beans

You saw in the preceding chapter that using BMP means that you’re responsible for coding the database calls needed to persist an entity bean. You do this using JDBC or an ORM framework that manages the mapping of object attributes to database tables. Whichever API you choose, a BMP bean class has to load and save its assigned entity object and that entity’s dependent objects as directed by the container. The container makes synchronization requests to an entity instance by invoking its callback methods (ejbLoad and ejbStore, among others). This approach gives you a great deal of control over how an entity bean is persisted and retrieved. The drawback is that you have to write and maintain the persistence code for ...