网络编程应用：基于UDP协议【实现聊天程序】--练习

使用UDP协议实现一个聊天程序

package UDP聊天程序;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Scanner;

public class Send {
public static void main(String[] args) {
System.out.println("发送端已启动！");

DatagramSocket socket=null;
Scanner scanner=new Scanner(System.in);
try {
//1.创建Datagramsocket对象
socket=new DatagramSocket();

while(true){
//2.要发送的数据
String string=scanner.nextLine();

//3.创建数据包
DatagramPacket packet=new DatagramPacket(string.getBytes(), string.getBytes().length,InetAddress.getLocalHost(),6666);
//4.发送数据
socket.send(packet);
//若我方发送了bye，马上结束聊天
if(string.equals("bye")){
System.out.println("bye,聊天结束！");
break;
}

//5.接收--接收端回复的数据
byte[] bs=new byte[1024];
DatagramPacket packet2=new DatagramPacket(bs, bs.length);
socket.receive(packet2);
String string2=new String(packet2.getData(), 0, packet2.getLength());
//若对方发送了bye，马上结束聊天
if(string2.equals("bye")){
System.out.println("bye,聊天结束！");
break;
}
System.out.println("接收端回复："+string2);
}

} catch (
fb15
SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally {
if(socket!=null){
socket.close();
}
}

}
}

package UDP聊天程序;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;
import java.util.Scanner;

public class Receive {
public static void main(String[] args) {
System.out.println("接收端已启动！");

DatagramSocket socket=null;
Scanner scanner=new Scanner(System.in);
try {
//1.创建Datagrams对象
socket=new DatagramSocket(6666);

while(true){
//2.创建数据包packet
byte[] buf=new byte[1024];
DatagramPacket packet=new DatagramPacket(buf, buf.length);
//3.接收数据
socket.receive(packet);
String string=new String(packet.getData(), 0, packet.getLength());
//若对方发送了bye，马上结束聊天
if(string.equals("bye")){
System.out.println("bye,聊天结束！");
break;
}
System.out.println("发送端说："+string);

//4.给发送端回复
String string2=scanner.nextLine();
DatagramPacket packet2=new DatagramPacket(string2.getBytes(), string2.getBytes().length,packet.getAddress(),packet.getPort());
socket.send(packet2);
//若我方发送了bye，马上结束聊天
if(string2.equals("bye")){
System.out.println("bye,聊天结束！");
break;
}
}
} catch (SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally {
if(socket!=null){
socket.close();
}
}

}
}