下面是 一个多线程,基于 UDP 用户数据报包 协议 的 控制台聊天小程序
import java.io.*;
import java.net.*;
class Send implements Runnable{
private DatagramSocket ds;
public DatagramPacket dp;
private byte [] sendBuf;
//private final int port=10086; // Receive Port
private final String ipAddress="192.168.10.1";
private InputStream in=System.in;
private BufferedReader bufr;
private InputStreamReader inpstr;
private String line; public Send(DatagramSocket ds){
this.ds=ds;
} public void run(){
try{
bufr=new BufferedReader(new InputStreamReader(in));
while((line=bufr.readLine())!=null){ sendBuf=line.getBytes();
dp=new DatagramPacket(sendBuf,sendBuf.length,InetAddress.getByName(ipAddress),Receive.port);
ds.send(dp);
if("end".equalsIgnoreCase(line)) break; }
}
catch(Exception e){
e.printStackTrace();
}
finally{
if(bufr!=null)
try{
bufr.close();
bufr=null;
}
catch(IOException ioe){
ioe.printStackTrace();
} }
} }
class Receive implements Runnable{
private DatagramSocket ds;
public static final int port=10087;
public DatagramPacket dp;
private InetAddress inetAddress;
private byte[] receiveBuf=new byte[1024];
private String receiveMsg; public void run(){
try{
ds=new DatagramSocket(port);
while(true){
dp=new DatagramPacket(receiveBuf,0,receiveBuf.length);
ds.receive(dp);
inetAddress=dp.getAddress();
receiveBuf=dp.getData();
receiveMsg=new String(receiveBuf,0,dp.getLength());
if("end".equalsIgnoreCase(receiveMsg)) break;
System.out.println(inetAddress.getHostAddress()+":"+dp.getPort()+": "+receiveMsg);
}
}
catch(Exception e){
e.printStackTrace();
} }
} class ChatDemo{
public static void main(String [] args) throws Exception{
new Thread(new Send(new DatagramSocket(10086))).start(); // send from 10086 port
new Thread(new Receive()).start();
}
} Demo 示例图