网络通信三要素：IP、端口、协议

import java.net.InetAddress;

 import java.net.UnknownHostException;

 /*

  * 网络通信三要素：IP、端口、协议

  */

 public class IPDemo {

    public static void main(String[] args) {

  try {

InetAddress i=InetAddress.getLocalHost();

System.out.println("address= "+i.getHostAddress());//address= 18.218.27.0

System.out.println("address= "+i.getHostName());//address= Len-P

System.out.println(i);//Lenovo-PC/18.218.27.0


InetAddress ia=InetAddress.getByName("www.baidu.com");//主机名

System.out.println("address= "+ia.getHostAddress());

System.out.println("address= "+ia.getHostName());



} catch (UnknownHostException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

 }

 }