Enterprise beans are the J2EE components that implement Enterprise JavaBeans (EJB) technology. Enterprise beans run in the EJB container, a runtime environment within the J2EE server (see Figure 1-5). Although transparent to the application developer, the EJB container provides system-level services such as transactions to its enterprise beans. These services enable you to quickly build and deploy enterprise beans, which form the core of transactional J2EE applications.
In This Chapter
- What Is an Enterprise Bean?
- Benefits of Enterprise Beans
- When to Use Enterprise Beans
- Types of Enterprise Beans
- What Is a Session Bean?
- State Management Modes
- When to Use Session Beans
- What Is an Entity Bean?
- What Makes Entity Beans Different from Session Beans?
- Container-Managed Persistence
- When to Use Entity Beans
- What Is a Message-Driven Bean?
- What Makes Message-Driven Beans Different from Session and Entity Beans?
- When to Use Message-Driven Beans
- Defining Client Access with Interfaces
- Remote Access
- Local Access
- Local Interfaces and Container-Managed Relationships
- Deciding on Remote or Local Access
- Performance and Access
- Method Parameters and Access
- The Contents of an Enterprise Bean
- Naming Conventions for Enterprise Beans
- The Life Cycles of Enterprise Beans
- The Life Cycle of a Stateful Session Bean
- The Life Cycle of a Stateless Session Bean
- The Life Cycle of an Entity Bean
- The Life Cycle of a Message-Driven Bean