public static function setClassName($registryClassName = 'JO_Registry') { if (self::$_registry !== null) { throw new Exception('Registry is already initialized'); } if (!is_string($registryClassName)) { throw new Exception("Argument is not a class name"); } if (!class_exists($registryClassName)) { require_once 'JO_Loader.php'; JO_Loader::loadClass($registryClassName); } self::$_registryClassName = $registryClassName; }