Java 获取一个机器的本地地址

public class IpDetector {
  public static String getIp() {
    try {
      Enumeration<NetworkInterface> em = NetworkInterface.getNetworkInterfaces();
      for(;em.hasMoreElements();) {
        NetworkInterface ni = em.nextElement();
        String nicName = ni.getName();
        if (nicName.startsWith("virbr")
            || nicName.startsWith("vboxnet")
            || nicName.startsWith("docker")
            ) {
          continue;
        }
        Enumeration<InetAddress> emAddr = ni.getInetAddresses();
        for(;emAddr.hasMoreElements();) {
          InetAddress addr = emAddr.nextElement();
          if (addr instanceof Inet4Address) {
            String addrStr = addr.getHostAddress();
            if (addrStr.startsWith("127.")) {
              continue;
            }
//            System.out.println("Address is "+addr.getHostAddress());
            return addrStr;
          }
        }
        System.out.println();
      }
    } catch (SocketException e) {
      e.printStackTrace();

    }
    return null;
  }

  public static void main(String[] args) {
    String ip = getIp();
    System.out.println("IP is "+ip);
  }
}