java local IP 가져오기

  public static String getLocalHostAddress(){
    String ip = null;
    try(
      final DatagramSocket socket = new DatagramSocket()){
      socket.connect(InetAddress.getByName("9.9.9.9"), 0);
      ip = socket.getLocalAddress().getHostAddress();
    }
    catch (Exception e){
      e.printStackTrace();
    }

    return ip;
  }