}
        if (ipString.charAt(start) == IPV6_DELIMITER) {
          // expand zeroes
          for (int i = 0; i < partsSkipped; i++) {
            rawBytes.putShort((short) 0);
          }

        } else {
          rawBytes.putShort(parseHextet(ipString, start, end));
        }
        start = end + 1;
      }
    } catch (NumberFormatException ex) {
      return null;
    }