java 获取本机的公网、外网ip

本机通过路由器联网，获取ip时获取的是路由器分配的IP。

获取公网的IP:

先找一个网站，可以获得本机的外网IP,如http://www.ip138.com/



检查元素，可以获得一个地址



直接访问这个网站进行截取

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.SocketException;
import java.net.URL;
import java.net.URLConnection;

public class Main {

public static void main(String[] args) throws SocketException {
for (int i = 0; i < 1000000; i++) {
int a=i;
new Runnable() {
public void run() {
System.out.println(a+"=========="+Main.getMyIP());
}
}.run();
}
}

private static String getMyIP() {
InputStream ins = null;
try {
URL url = new URL("http://1212.ip138.com/ic.asp");
URLConnection con = url.openConnection();
ins = con.getInputStream();
InputStreamReader isReader = new InputStreamReader(ins, "GB2312");
BufferedReader bReader = new BufferedReader(isReader);
StringBuffer webContent = new StringBuffer();
String str = null;
while ((str = bReader.readLine()) != null) {
webContent.append(str);
}
// System.out.println(webContent);
int start = webContent.indexOf("[") + 1;
int end = webContent.indexOf("]");
return webContent.substring(start, end);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (ins != null) {
try {
ins.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return "";
}
}