Question

我在本机上，想写一个java程序获取我本机的外网ip地址，如何搞

Answer 1

import java.net.*;

public class Test {

public static void main(String[] args) throws UnknownHostException {
String IP = null;
String host = null;
InetAddress ia;

ia = InetAddress.getLocalHost();
host = ia.getHostName();// 获取计算机名字
IP = ia.getHostAddress();// 获取IP

System.out.println(host);
System.out.println(IP);
}

}

Answer 2

private String getIpAddr() {
String ipAddress = null;
//ipAddress = this.getRequest().getRemoteAddr();
ipAddress = this.getRequest().getHeader("x-forwarded-for");
if(ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
ipAddress = this.getRequest().getHeader("Proxy-Client-IP");
}
if(ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
ipAddress = this.getRequest().getHeader("WL-Proxy-Client-IP");
}
if(ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
ipAddress = this.getRequest().getRemoteAddr();
if(ipAddress.equals("127.0.0.1")){
//根据网卡取本机配置的IP
InetAddress inet=null;
try {
inet = InetAddress.getLocalHost();
} catch (UnknownHostException e) {
e.printStackTrace();
}
ipAddress= inet.getHostAddress();
}

}

//对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
if(ipAddress!=null && ipAddress.length()>15){ //"***.***.***.***".length() = 15
if(ipAddress.indexOf(",")>0){
ipAddress = ipAddress.substring(0,ipAddress.indexOf(","));
}
}
return ipAddress;
}