code: public static ValueRange of(long min, long max) {
          if (min > max) {
              throw new IllegalArgumentException("Minimum value must be less than maximum value");
          }
          return new ValueRange(min, min, max, max);
      }
docs: Obtains a fixed value range.
  <p>
  This factory obtains a range where the minimum and maximum values are fixed.
  For example, the ISO month-of-year always runs from 1 to 12.
  
  @param min  the minimum value
  @param max  the maximum value
  @return the ValueRange for min, max, not null
  @throws IllegalArgumentException if the minimum is greater than the maximum