code: protected final boolean isPatternValid() {
  
          switch (getPatternType()) {
              case DAILY:
                  return isEveryWorkingDay() || isIntervalValid();
              case WEEKLY:
                  return isIntervalValid() && isWeekDaySet();
              case MONTHLY:
                  return isIntervalValid() && isWeekDaySet() ? isWeekOfMonthSet() : isDayOfMonthValid();
              case YEARLY:
                  return isMonthSet() && isWeekDaySet() ? isWeekOfMonthSet() : isDayOfMonthValid();
              case INDIVIDUAL:
              case NONE:
                  return true;
              default:
                  return false;
          }
      }
docs: Checks, if all values necessary for a specific pattern are valid.
  @return a flag, indicating if all values required for the pattern are valid.