/**
  * @param string $dir
  */
 public static function addResourceDir($dir)
 {
     if (in_array($dir, static::$dirs)) {
         return;
     }
     $iterator = new \FilesystemIterator($dir, \FilesystemIterator::SKIP_DOTS);
     foreach ($iterator as $value) {
         if (!$iterator->isFile()) {
             continue;
         }
         list($domain, $locale, $format) = explode('.', $iterator->getBasename(), 3);
         static::$translator->addResource($format, $iterator->getRealPath(), $locale, $domain);
     }
     static::$dirs[] = $dir;
 }