/**
  * @return AdminError404DAO
  */
 public static function instance()
 {
     if (self::$instance === null) {
         self::$instance = new self();
     }
     return self::$instance;
 }
 public static function delete_404_error($id)
 {
     try {
         $error = AdminError404DAO::instance()->find_by_id($id);
         AdminError404DAO::instance()->delete($error);
     } catch (ObjectNotFoundException $exception) {
     }
 }