code: private final void computeGregorianAndDOWFields(int julianDay) {
          computeGregorianFields(julianDay);
  
          // Compute day of week: JD 0 = Monday
          int dow = fields[DAY_OF_WEEK] = julianDayToDayOfWeek(julianDay);
  
          // Calculate 1-based localized day of week
          int dowLocal = dow - getFirstDayOfWeek() + 1;
          if (dowLocal < 1) {
              dowLocal += 7;
          }
          fields[DOW_LOCAL] = dowLocal;
      }
docs: Compute the Gregorian calendar year, month, and day of month from
  the given Julian day.  These values are not stored in fields, but in
  member variables gregorianXxx.  Also compute the DAY_OF_WEEK and
  DOW_LOCAL fields.