Configuring an Around Invoke Interceptor Method on an EJB 3.0 MDB

You can specify one nonbusiness method as the interceptor method for an EJB 3.0 message-driven bean. Each time the onMessage method is invoked, OC4J intercepts the invocation and invokes the interceptor method. The onMessage method invocation proceeds only if the interceptor method returns InvocationContext.proceed().

An interceptor method has the following signature:

Object <METHOD>(InvocationContext) throws Exception

An interceptor method may have public, private, protected, or package level access, but must not be declared as final or static.

You can specify this method on the EJB 3.0 message-driven bean class (see "Using Annotations") or on an interceptor class that you associate with an EJB 3.0 message-driven bean (see "Configuring an Around Invoke Interceptor Method on an Interceptor Class of an EJB 3.0 MDB").

For more information, see "Understanding EJB 3.0 Interceptors".

Using Annotations

Example 10-11 shows how to designate a method of a message-driven bean class as an interceptor method using the @AroundInvoke annotation. Each time the onMessage method is invoked, OC4J intercepts the invocation and invokes the interceptor method myInterceptor. The onMessage method invocation proceeds only if the interceptor method returns InvocationContext.proceed().

Example 10-11 @AroundInvoke in an EJB 3.0 Message-Driven Bean

@MessageDriven
public class MessageLogger implements MessageListene {
    @Resource javax.ejb.MessageDrivenContext mc;

    public void onMessage(Message message) {
    ....
    }

    @AroundInvoke
    public Object myInterceptor(InvocationContext ctx) throws Exception  {
        if (!userIsValid(ctx. getEJBContext().getCallerPrincipal())) {
            throw new SecurityException(
                "Caller: '" + ctx.getEJBContext().getCallerPrincipal().getName() +
                "' does not have permissions for method " + ctx.getMethod()
            );
        }
        return ctx.proceed();
    }
}