public < T > T doAs ( final PrivilegedExceptionAction < T > action ) throws Exception { LOG . log ( Level . FINE , "{0} execute {1}" , new Object [ ] { this , action } ) ; return this . proxyUGI == null ? action . run ( ) : this . proxyUGI . doAs ( action ) ; }
Execute the privileged action as a given user . If user credentials are not set execute the action outside the user context .