private function fetchFromCache(User $user)
    {
        return $this->hasCache($user) ? self::$cache[$user->getId()] : null;
    }
private function fetchFromCache(User $user)
    {
        return $this->hasCache($user) ? self::$cache[$user->getId()] : null;
    }
private function fetchFromCache ( User $ user ) { return $ this -> hasCache ( $ user ) ? self :: $ cache [ $ user -> getId ( ) ] : null ; }
Fetchs ACL from cache for users.

@param User $user

@return null || \ACL
Fetchs ACL from cache for users .