class MacAddress implements Comparable<MacAddress>, Serializable {

  public static @Nonnull MacAddress of(long longVal) {
    checkArgument(
        longVal == (longVal & 0xFFFFFFFFFFFFL),
        "Cannot create MAC address from invalid long value: %s",
        longVal);
    return new MacAddress(longVal);
  }

  private  MacAddress(long longVal);

}