/**
* Checks if a user - optionally with at least the given user permissions level -
* is logged into the system.
* @param integer $userLevel Optional. Minimum required user level. If a user is logged in but does not have at least this user level, false will be returned nonetheless.
* @return boolean True if a user is currently logged in.
*/
public function isLoggedIn()
{
return $this->user ? $this->user->isLoggedIn() : false;
}