Java getting my IP address

    String ip;
    try {
        Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
        while (interfaces.hasMoreElements()) {
            NetworkInterface iface = interfaces.nextElement();
            // filters out 127.0.0.1 and inactive interfaces
            if (iface.isLoopback() || !iface.isUp())
                continue;

            Enumeration<InetAddress> addresses = iface.getInetAddresses();
            while(addresses.hasMoreElements()) {
                InetAddress addr = addresses.nextElement();
                ip = addr.getHostAddress();
                System.out.println(iface.getDisplayName() + " " + ip);
            }
        }
    } catch (SocketException e) {
        throw new RuntimeException(e);
    }

The NetworkInterface class contains all the relevant methods, but be aware that there's no such thing as "my IP". A machine can have multiple interfaces and each interface can have multiple IPs.

You can list them all with this class but which interface and IP you choose from the list depends on what you exactly need to use this IP for.

(InetAddress.getLocalHost() doesn't consult your interfaces, it simply returns constant 127.0.0.1 (for IPv4))

Let's ask AWS

URL url = new URL("http://checkip.amazonaws.com/");
BufferedReader br = new BufferedReader(new InputStreamReader(url.openStream()));
System.out.println(br.readLine());

EDIT

Before you downvote, I'm well aware this is not a java solution. Its a general solution for any programming language. The other solutions don't work as well for me. Also I believe the easier way of knowing your IP is to go on the internet. It can be any site, the server can return back your client ip that it got in the request. You can set up your own endpoint for it.

Had the same problem, found the solution on this page: http://mrhawy.blogspot.it/2012/05/how-to-get-your-external-ip-address-in.html

    public String getIpAddress() throws MalformedURLException, IOException {
  URL myIP = new URL("http://api.externalip.net/ip/");
  BufferedReader in = new BufferedReader(
                       new InputStreamReader(myIP.openStream())
                      );
  return in.readLine();
  }

had some troubles with this code on the long run, several times in a week the server just won't reply.

new solution:

public static String getIpAddress() 
{ 
        URL myIP;
        try {
            myIP = new URL("http://api.externalip.net/ip/");

            BufferedReader in = new BufferedReader(
                    new InputStreamReader(myIP.openStream())
                    );
            return in.readLine();
        } catch (Exception e) 
        {
            try 
            {
                myIP = new URL("http://myip.dnsomatic.com/");

                BufferedReader in = new BufferedReader(
                        new InputStreamReader(myIP.openStream())
                        );
                return in.readLine();
            } catch (Exception e1) 
            {
                try {
                    myIP = new URL("http://icanhazip.com/");

                    BufferedReader in = new BufferedReader(
                            new InputStreamReader(myIP.openStream())
                            );
                    return in.readLine();
                } catch (Exception e2) {
                    e2.printStackTrace(); 
                }
            }
        }

    return null;
}