public static IpPrefix valueOf(int address, int prefixLength) {
        return new IpPrefix(IpAddress.valueOf(address), prefixLength);
    }
@Test
    public void testEqualityIPv4() {
        new EqualsTester()
            .addEqualityGroup(IpPrefix.valueOf("1.2.0.0/24"),
                              IpPrefix.valueOf("1.2.0.0/24"),
                              IpPrefix.valueOf("1.2.0.4/24"))
            .addEqualityGroup(IpPrefix.valueOf("1.2.0.0/16"),
                              IpPrefix.valueOf("1.2.0.0/16"))
            .addEqualityGroup(IpPrefix.valueOf("1.2.0.0/32"),
                              IpPrefix.valueOf("1.2.0.0/32"))
            .addEqualityGroup(IpPrefix.valueOf("1.3.0.0/24"),
                              IpPrefix.valueOf("1.3.0.0/24"))
            .addEqualityGroup(IpPrefix.valueOf("0.0.0.0/0"),
                              IpPrefix.valueOf("0.0.0.0/0"))
            .addEqualityGroup(IpPrefix.valueOf("255.255.255.255/32"),
                              IpPrefix.valueOf("255.255.255.255/32"))
            .testEquals();
    }