@Override
  public ChronoLocalDate<JapaneseChrono> date(Era<JapaneseChrono> era, int yearOfEra, int month, int dayOfMonth) {

    if (era instanceof JapaneseEra == false) {
      throw new DateTimeException("Era must be JapaneseEra");
    }
    return JapaneseDate.of((JapaneseEra) era, yearOfEra, month, dayOfMonth);
  }