Now in order to get access to Principal information from action you have to add servlet-config interceptor to your action or get HttpServletRequest from ActionContext. In any case your action become bound to Servlet API that makes it diffucult to test it.

I have created an interceptor, Interface and helper class.

Interceptor allows access to the following HttpServletRequest methods: getUserPrincipal(), isUserInRole(), getRemoteUser().

Comments, sugestions and reviews are welcome.

Still have some questions:
1. Should I add ability to get access to HttpServletRequest.getAuthType() method.