在JavaFX桌面应用程序中获取远程IP地址

Question

I need to obtain the remote IP address of a user in my JavaFX desktop app. I am using Spring to deal with things such as authentication (my program uses database connection). I do know how to get IP address from http request when using Java Servlet, the problem is I don't have one in my app. I considered using some kind of website that checks IP, and simply getting the content of the html parsed to a string, but I have to do everything locally / independent from any external source.

I appreciate any kind of help, thanks in advance

EDIT: Some additional info that might help: I am not using sockets, my app is supposed to be used by end user, and only connection it has is the connection with MySQL database from which it gets some content. I need to retrieve the IP address of user at the moment of logging in, to put said IP address together with port to a particular table in my database.

Answer 1

As suggested in the comments, the only way to do this is to query an external source. You can fairly easily write some code to do this, eg

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;


public class RealIPScraper {
    private static final String URL_STRING = "http://www.realip.info/api/p/realip.php" ;

    private static final Pattern pattern = Pattern.compile("\\{\"IP\":\"(?<ip>.*)\"\\}");

    public static String getIP() throws IOException {
        URL url = new URL(URL_STRING);
        try (BufferedReader in = new BufferedReader(new InputStreamReader(url.openConnection().getInputStream()))) {
            String content = String.join("\n", in.lines().collect(Collectors.toList()));
            Matcher matcher = pattern.matcher(content);
            if (matcher.matches()) {
                return matcher.group("ip");
            } else {
                return "No ip found";
            }
        }
    }

}