*
   * @param ip {@link Inet6Address} to be examined for embedded IPv4 compatible address format
   * @return {@code true} if the argument is a valid "compat" address
   */
  public static boolean isCompatIPv4Address(Inet6Address ip) {
    if (!ip.isIPv4CompatibleAddress()) {
      return false;
    }

    byte[] bytes = ip.getAddress();
    if ((bytes[12] == 0)
        && (bytes[13] == 0)

    for (String nonCompatAddress : nonCompatAddresses) {
      InetAddress ip = InetAddresses.forString(nonCompatAddress);
      assertFalse(InetAddresses.isCompatIPv4Address((Inet6Address) ip));
      assertThrows(
          "IllegalArgumentException expected for '" + nonCompatAddress + "'",
          IllegalArgumentException.class,