How do I access the Principal in a Message Driven Bean?

Question

In the onMessage method of a MDB, how can I retrieve the name of the JAAS User Principal that initiated the request? My application is using Servlet login and a jdbcRealm.

I have considered adding this as a Message Property, but I would rather ensure that this is handled by JAAS.

Answer 1

It is handled inherently, all that you have to do is to inject and use MessageDrivenContext:

..
@Resource
private MessageDrivenContext mdc;

public void onMessage(Message message) {
    Principal principal = mdc.getCallerPrincipal();
    System.out.println(principal.getName());
    //ALTERNATIVELY, YOU CAN USE A METHOD mdc.isCallerInRole("<role name>");
}