docs: private void calculate(String mask) {
          Matcher matcher = cidrPattern.matcher(mask);
  
          if (matcher.matches()) {
              matchAddress(matcher);
  
              /* Create a binary netmask from the number of bits specification /x */
              rangeCheck(Integer.parseInt(matcher.group(5)), 0, NBITS);
          } else {
              throw new IllegalArgumentException("Could not parse [" + mask + "]");
          }
      }