public static IPMappingAddress ipv4MappingAddress(IpPrefix ip) {
        return new IPMappingAddress(ip, MappingAddress.Type.IPV4);
    }
@Test
    public void testIpv4MappingAddressMethod() {
        IpPrefix ip = IpPrefix.valueOf("1.2.3.4/24");
        MappingAddress mappingAddress = MappingAddresses.ipv4MappingAddress(ip);
        IPMappingAddress ipMappingAddress =
                checkAndConvert(mappingAddress,
                                MappingAddress.Type.IPV4,
                                IPMappingAddress.class);
        assertThat(ipMappingAddress.ip(), is(equalTo(ip)));
    }