import java.net.DatagramPacket;import java.net.DatagramSocket;/** * 接收线程 *  * @author xiaoduc * */public class ReceiveThread extends Thread {    private DatagramSocket ds;    public ReceiveThread(int port) {        super();        try {            this.ds = new DatagramSocket(port);        } catch (Exception e) {            e.printStackTrace();        }    }        @Override    public void run() {        try {            //创建byte数组            byte[] buff=new byte[1024];            //创建一个数据包对象            DatagramPacket dp=new DatagramPacket(buff, 1024);            //永真循环            while(true){                ds.receive(dp);//接收消息                String str=new String(dp.getData(),0,dp.getLength());//得到数据                System.out.println("接收："+str);//打印消息            }        } catch (Exception e) {            e.printStackTrace();        }finally {            ds.close();        }    }}

 

import java.io.BufferedReader;import java.io.InputStreamReader;import java.net.DatagramPacket;import java.net.DatagramSocket;import java.net.InetAddress;/** * 发送线程类 * @author xiaoduc * */public class SendThread extends Thread{    private DatagramSocket ds;    private int sendPort;        public SendThread(int port,int sendPort){        super();        this.sendPort=sendPort;        try {            this.ds=new DatagramSocket(port);        } catch (Exception e) {            e.printStackTrace();        }    }        @Override    public void run() {        try {            //循环接收用户输入            BufferedReader br=new BufferedReader(new InputStreamReader(System.in));            String str=null;            while((str=br.readLine())!=null){                //创建Datagrampacket对象                DatagramPacket dp=new DatagramPacket(str.getBytes(), 0,str.length(),InetAddress.getByName("localhost"),sendPort);                ds.send(dp);//发送数据                System.out.println("发送："+str);//打印            }        } catch (Exception e) {            e.printStackTrace();        }finally {            ds.close();        }    }}

 

public class Chat {    public static void main(String[] args) {        //启动发送线程        new SendThread(1091, 1099).start();            }}

 

public class ReceiveChat {    public static void main(String[] args) {        //启动接收线程        new ReceiveThread(1099).start();    }}