code: public function parseTimestamp($format)
      {
          $time  = intval($format);
          $year  = date("Y", $time);
          $month = date("n", $time);
          $date  = date("d", $time);
          $hour  = date("H", $time);
          $min   = date("i", $time);
          $sec   = date("s", $time);
          return new Timestamp($year, $month, $date, $hour, $min, $sec);
      }
docs: 指定されたタイムスタンプを Timestamp に変換します.
  @param  string $format タイムスタンプ
  @return Timestamp      変換結果