public static MacAddress valueOf(final String address) {
        if (!isValid(address)) {
            throw new IllegalArgumentException(
                    "Specified MAC Address must contain 12 hex digits"
                            + " separated pairwise by :'s.");
        }
        final String[] elements = address.split(":");
        final byte[] addressInBytes = new byte[MacAddress.MAC_ADDRESS_LENGTH];
        for (int i = 0; i < MacAddress.MAC_ADDRESS_LENGTH; i++) {
            final String element = elements[i];
            addressInBytes[i] = (byte) Integer.parseInt(element, 16);
        }

        return new MacAddress(addressInBytes);
    }
@Test(expected = IllegalArgumentException.class)
    public void testValueOfInvalidByte() throws Exception {
        MacAddress.valueOf(INVALID_BYTE);
    }