通过Java获取本地主机的外网地址, 该实验通过网址chinaz获取。

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

/**
 * Created with IntelliJ IDEA.
 * Description:
 *
 * @author: SweiPC
 * @data: 2022-09-18 12:06
 */
public class GetHostIP {

    public static void main(String[] args) throws IOException {
        String ip = null;
        String chinaz = "https://ip.chinaz.com";
        StringBuilder inputLine = new StringBuilder();
        String read = "";
        URL url = null;
        HttpURLConnection urlConnection = null;
        BufferedReader in = null;
        try {
            url = new URL(chinaz);
            urlConnection = (HttpURLConnection) url.openConnection();
            in = new BufferedReader(new InputStreamReader(urlConnection.getInputStream(), "UTF-8"));
            while ((read = in.readLine()) != null) {
                inputLine.append(read + "\r\n");
            }
            Pattern p = Pattern.compile("\\<dd class\\=\"fz24\">(.*?)\\<\\/dd>");
            Matcher m = p.matcher(inputLine.toString());
            if (m.find()) {
                String ipstr = m.group(1);
                ip = ipstr;
            }
        } finally {
            if (in != null) {
                in.close();
            }
        }
        if (ip == null) {
            throw new RuntimeException();
        }
        System.out.println(ip);
    }
}