### Question:
NetUtil { public static String toIpAddress(SocketAddress address) { InetSocketAddress inetSocketAddress = (InetSocketAddress) address; return inetSocketAddress.getAddress().getHostAddress(); }  static String toStringAddress(SocketAddress address); static String toIpAddress(SocketAddress address); static String toStringAddress(InetSocketAddress address); static InetSocketAddress toInetSocketAddress(String address); static long toLong(String address); static String getLocalIp(); static String getLocalHost(); static InetAddress getLocalAddress(); static void validAddress(InetSocketAddress address); static boolean isValidIp(String ip, boolean validLocalAndAny);  }### Answer:
@Test public void testToIpAddress() throws UnknownHostException { assertThat(NetUtil.toIpAddress(ipv4)).isEqualTo(ipv4.getAddress().getHostAddress()); assertThat(NetUtil.toIpAddress(ipv6)).isEqualTo(ipv6.getAddress().getHostAddress()); }