/**
  * @param string $unicode_
  * @param \Components\Io_Charset $charset_
  *
  * @return string
  */
 public function unicodeDecode($unicode_, Io_Charset $charset_ = null)
 {
     if (null === $charset_) {
         $charset_ = Io_Charset::UTF_16_BE();
     }
     self::$m_convertImplTo = $this;
     self::$m_convertImplFrom = $charset_;
     return preg_replace_callback('/(?:\\\\u[0-9a-fA-Z]{4})+/', function ($string_) {
         return Io_Charset::__unicodeDecodeConvertEncodingImpl(pack('H*', strtr($string_[0], ['\\u' => ''])));
     }, $unicode_);
 }