code: public boolean containsRange(Range<T> otherRange) {
      if (otherRange == null) { return false; }
      return contains(otherRange.min) && contains(otherRange.max);
    }
docs: <p>
  Checks whether this range contains all the elements of the specified range. This method may
  fail if the ranges have two different comparators or element types.
  </p>