docs: @SuppressWarnings("deprecation")
      public BigDecimal getDecimalMillis()
      {
          switch (this._precision) {
          case YEAR:
          case MONTH:
          case DAY:
          case MINUTE:
          case SECOND:
          case FRACTION:
              long millis = Date.UTC(this._year - 1900, this._month - 1, this._day, this._hour, this._minute, this._second);
              BigDecimal dec = BigDecimal.valueOf(millis);
              if (_fraction != null) {
                  dec = dec.add(this._fraction.movePointRight(3));
              }
              return dec;
          }
          throw new IllegalArgumentException();
      }