defaultRules() protected méthode

protected defaultRules ( )
 protected function defaultRules()
 {
     $rules = [];
     if (class_exists('\\rock\\mongodb\\sanitize\\rules\\MongoIdRule')) {
         $rules['mongoId'] = \rock\mongodb\sanitize\rules\MongoIdRule::className();
     }
     return $rules + parent::defaultRules();
 }