code: public boolean isHoliday(String dateString) {
          boolean isHoliday = false;
          for (Holiday date : EquivalenceClassTransformer.HOLIDAYS) {
              if (convertToReadableDate(date.forYear(Integer.parseInt(dateString.substring(0, 4)))).equals(dateString)) {
                  isHoliday = true;
              }
          }
          return isHoliday;
      }
docs: Checks if the date is a holiday
  
  @param dateString the date
  @return true if it is a holiday, false otherwise