The idea behind interceptors is to separate common, or cross-cutting, code from business methods. Examples of such common code are logging, auditing, performance monitoring, or security checks. Such aspects are shared among business methods and are often tangential to any business logic. Instead of cluttering business methods with cross-cutting code, any such code is encapsulated in separate methods or classes called interceptors. Whenever a business method is invoked by an EJB container, its associated interceptors are automatically invoked first.

In this chapter we will cover:

Interceptors are associated with Aspect Oriented Programming (AOP) and is a new feature introduced in version 3.0 of the EJB specification.

EJB 3 provides the ability to apply custom made interceptors to the business methods of session and message-driven beans. These interceptors take the form of methods annotated...