@Test public void shouldCalculateCommonPrefixLength() { Ipv4 ipv4 = Ipv4.of("192.168.0.0"); assertEquals(0, ipv4.getCommonPrefixLength(Ipv4.of("0.0.0.0"))); assertEquals(16, ipv4.getCommonPrefixLength(Ipv4.of("192.168.255.255"))); assertEquals(32, ipv4.getCommonPrefixLength(Ipv4.of("192.168.0.0"))); }