IT. Expert System.

@Documented
 @Retention(value=RUNTIME)
 @Target(value=METHOD)
public @interface PreDestroy

The PreDestroy annotation is used on methods as a callback notification to signal that the instance is in the process of being removed by the container. The method annotated with PreDestroy is typically used to release resources that it has been holding. This annotation MUST be supported by all container managed objects that support PostConstruct except the application client container in Java EE 5. The method on which the PreDestroy annotation is applied MUST fulfill all of the following criteria:

• The method MUST NOT have any parameters except in the case of interceptors in which case it takes an InvocationContext object as defined by the Interceptors specification.
• The method defined on an interceptor class MUST HAVE one of the following signatures:

  void <METHOD>(InvocationContext)

  Object <METHOD>(InvocationContext) throws Exception

  Note: A PreDestroy interceptor method must not throw application exceptions, but it may be declared to throw checked exceptions including the java.lang.Exception if the same interceptor method interposes on business or timeout methods in addition to lifecycle events. If a PreDestroy interceptor method returns a value, it is ignored by the container.

• The method defined on a non-interceptor class MUST HAVE the following signature:

  void <METHOD>()

• The method on which PreDestroy is applied MAY be public, protected, package private or private.
• The method MUST NOT be static.
• The method MAY be final.
• If the method throws an unchecked exception it is ignored except in the case of EJBs where the EJB can handle exceptions.