@Override
  protected List<DateTimeField> validFields() {

    DateTimeField[] array = { DAY_OF_WEEK, ALIGNED_DAY_OF_WEEK_IN_MONTH, ALIGNED_DAY_OF_WEEK_IN_YEAR, DAY_OF_MONTH,
        DAY_OF_YEAR, EPOCH_DAY, ALIGNED_WEEK_OF_MONTH, ALIGNED_WEEK_OF_YEAR, MONTH_OF_YEAR, EPOCH_MONTH, YEAR_OF_ERA,
        YEAR, ERA, OFFSET_SECONDS, JulianDayField.JULIAN_DAY, JulianDayField.MODIFIED_JULIAN_DAY,
        JulianDayField.RATA_DIE, };
    return Arrays.asList(array);
  }