code: public void init(BaseField field, BaseField fldSource, DateTimeField fldStartDate, int lYears, int lMonths, int lDays, boolean bCalcIfNull)
      {
          super.init(field, fldSource, null, true, false);
          m_lYears = lYears;
          m_lMonths = lMonths;
          m_lDays = lDays;
          m_fldStartDate = fldStartDate;
          m_bCalcIfNull = bCalcIfNull;
      }
docs: Constructor.
  @param field The basefield owner of this listener (usually null and set on setOwner()).
  @param fldSource The field with the source number of days to use as an offset.
  @param lYears Offset by this number of years.
  @param lMonths Offset by this number of months.
  @param lDays Offset by this number of days.