public DayModel getDefaultDay(Reference cal) {

    for (DayModel day : cal.getDefaultWeekDays()) {
      if (day.getDefaultDay()) {
        return day;
      }
    }
    return null;
  }
 private void assignWorkHourRanges(DayModel day, DayModel defaultDay) {
   day.setWorkHourRanges(new LinkedHashSet<WorkHourRange>());
   for (WorkHourRange range : defaultDay.getWorkHourRanges()) {
     WorkHourRange newRange = new WorkHourRange();
     newRange.setDay(day);
     newRange.setFromTime(range.getFromTime());
     newRange.setToTime(range.getToTime());
     day.getWorkHourRanges().add(newRange);
   }
 }