code: @Override
    public IVersionRange invert() {
      if (ranges.size() == 2) {
        IVersionRange irange1 = ranges.first().invert();
        IVersionRange irange2 = ranges.last().invert();
        return new AndRange(irange1, irange2);
      }
  
      throw new UnsupportedOperationException();
    }
docs: /*
  (non-Javadoc)
  @see net.ossindex.version.impl.AbstractCommonRange#invert()