if (req.getString(LOGIN_USER_NAME) != null && req.getString(LOGIN_PASSWORD) != null)
{
String username = req.getString(LOGIN_USER_NAME);
String password = req.getString(LOGIN_PASSWORD);
LoginStatus login = FrontControllerAuthenticator.login(req, username, password);
if (login == LoginStatus.ALREADY_LOGGED_IN)
{
// reach this by using the 'back' button of the browser and
// click Login again :)