Chapter 3. Building business logic with session beans

At the heart of any enterprise application is its business logic. In an ideal world, application developers should mainly be concerned with implementing business logic, while concerns like presentation, persistence, and integration should largely be window dressing. From this perspective, session beans are the most important part of the EJB technology because their purpose in life is to model high-level business processes.

If you think of a business system as a horse-drawn chariot carrying the Greco-Roman champion to battle, session beans are the driver. Session beans utilize data and system resources (the chariot and horses) to implement the goals of the user (the champion) using business logic (the skills and judgment of the driver). For this and other reasons, sessions beans, particularly stateless session beans, have been popular, even despite the problems of EJB 2. EJB 3 makes this vital bean type much easier to use and adds some important functionality.

3.1. Getting to know session beans

3.2. Stateless session beans

3.3. Stateful session beans

3.4. Singleton session beans

3.5. Asynchronous session beans

3.6. Summary