WAS v8.5 > Develop applications > Develop EJB applications > Develop EJB 3.x enterprise beansEJB 3.0 specification
This topic describes the EJB 3.0 specification that is the foundation of the development and application programming model for the EJB 3.0 applications. Read this topic for a brief overview of the EJB 3.0 specification.
The EJB 3.0 specification has justifiably been called the most important upgrade to the Java Platform, Enterprise Edition 5 (Java EE 5) programming model. The EJB 3.0 specification represents simplification and streamlining of the business logic and persistence programming models used in Java EE. The ultimate source of information is the specification, which is available on the Oracle website.
While the Java Persistence API (JPA) replacement is called an entity class, it should not be confused with entity enterprise beans. A JPA entity is not an enterprise bean and is not required to run in an EJB container.
The EJB 3.0 specification is organized into three areas:
- EJB core contracts and requirements
- EJB 3.0 simplified API
- JPA
The EJB core contracts and requirements define the service provider interfaces (SPIs) between the enterprise bean instance and the enterprise bean container. This part of the specification also includes the APIs between the enterprise bean provider and the enterprise bean container, protocols, component and container contracts, system level issues, infrastructure services provided by the container to the bean and other information about development packaging and deployment for session, message-driven, and entity beans.
The EJB 3.0 simplified API provides information about simplifying EJB APIs and SPIs that exist from previous EJB specification versions.
The JPA document introduces the Plain Old Java Object (POJO)-style persistent entity development guidelines.
Another good source for EJB 3.0 information is Mastering Enterprise JavaBeans 3.0, Fourth Edition. This edition features chapters on session beans and message-driven beans, EJB, and Java EE integration and advanced persistence concepts. Also included is coverage of the JPA and POJO using entities with the EJB programming model.
Related concepts:
New features
Related
Develop enterprise beans
Tasks: Using enterprise beans in applications
Tasks: Storing and retrieving persistent data with the JPA API
Change applications to WebSphere version specific setRollbackOnly behavior
Related information:
Mastering Enterprise JavaBeans 3.0, Fourth Edition