import java.net.*;public class NetDemo {    public static void main(String[] args) throws Exception{        String str = "172.20.223.120";        String[] ipStr = str.split("\\.");        byte[] ipBuf = new byte[4];        for(int i = 0; i < 4; i++){            ipBuf[i] = (byte)(Integer.parseInt(ipStr[i])&0xff);        }        InetAddress ia = InetAddress.getByAddress("hao.wen",ipBuf);        System.out.println(ia);    }}