code: protected void getUser(final Session session, final AuthProviderListener listener) {
  		Request.executeMeRequestAsync(session, new Request.GraphUserCallback() {
  			// callback after Graph API response with user object
  			@Override
  			public void onCompleted(GraphUser user, Response response) {
  				if(response.getError() != null) {
  					handleError(response.getError().getException(), listener);
  				}
  				else if (user != null) {
  					handleResult(session, user, listener);
  				}
  			}
  		});
  	}
docs: so we can mock