写一个基于UDP协议的聊天小程序

 

分类： Java

UDP是无连接的传输协议，所以对于写聊天程序来说不需要太多考虑同步等问题，下面是我写的一个UDP聊天程序，界面是用SWING简单做的。

1.服务器端口（其实UDP没有什么服务器端的说法，这里只是作为区分）

package mytest;

import java.awt.*;
import java.awt.event.*;
import java.io.IOException;
import java.net.*;
import javax.swing.*;

/**
 *
 * @author hh
 *
 */

public class UdpChatServer extends JFrame
{
    JTextField putDiag;
    JTextArea showDiag;
    StringBuffer stb = new StringBuffer();
    
    
    public UdpChatServer()
    {
    this.setBounds(300, 300, 400, 500);
    this.setTitle("聊天界面s");

    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
    
    public void showMain()
    {
    JPanel jp = new JPanel();
    jp.setLayout(new BorderLayout());
    
    showDiag = new JTextArea(20,50);
    showDiag.setEditable(false);
    putDiag = new JTextField();

    putDiag.addActionListener(new tfListener());
    
    jp.add(showDiag,BorderLayout.NORTH);
    jp.add(putDiag, BorderLayout.SOUTH);
    
    Container containerPane = getContentPane();
    containerPane.add(jp);

    setVisible(true);
    
    while(true)  //总是监听接收端口
     recieveData();
    }
    
    private class tfListener implements ActionListener
    {
    public void actionPerformed(ActionEvent e)
    {
     String str = putDiag.getText().trim();   
     sendData(str);
     stb.append("我说:"+str+" ");
     showDiag.setText(stb.toString());
     putDiag.setText("");  
    }
    }
   


    public void sendData(String str)
    {
    byte[] dataArray = new byte[1000];
    dataArray = str.getBytes();
    try
    {
     InetAddress ia = InetAddress.getLocalHost();
     DatagramSocket ds = new DatagramSocket(8889);
     DatagramPacket dp = new    DatagramPacket(dataArray,dataArray.length,ia,8881);
    
     ds.send(dp); //从自方8889端口发送到对方的8881端口
     ds.close();
    } catch (UnknownHostException e)
    {
     e.printStackTrace();
    } catch (SocketException e)
    {
     e.printStackTrace();
    } catch (IOException e)
    {
     e.printStackTrace();
    }
    }
   


    public void recieveData()
    {
    byte[] dataArray = new byte[1000];
    try
    {
     DatagramSocket ds = new DatagramSocket(8888);
     DatagramPacket dp = new DatagramPacket(dataArray,dataArray.length);
    
     ds.receive(dp); //等待接受从自方8888端口接受来的数据

     ds.close();
     stb.append(new String(dataArray).trim()+" ");
     showDiag.setText(stb.toString());
    
    } catch (SocketException e)
    {
     e.printStackTrace();
    } catch (IOException e)
    {
     e.printStackTrace();
    }
    }
    
    public static void main(String[] args)
    {
    UdpChatServer ucs = new UdpChatServer();
    ucs.showMain();
    
    }
}


2.客户端口

package mytest;

import java.awt.*;
import java.awt.event.*;
import java.io.IOException;
import java.net.*;
import javax.swing.*;

/**
 *
 * @author hh
 *
 */
public class UdpChatClient extends JFrame
{
    JTextField putDiag;
    JTextArea showDiag;
    StringBuffer stb = new StringBuffer();;
    
    public UdpChatClient()
    {
    this.setBounds(300, 300, 400, 500);
    this.setTitle("聊天界面c");
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
   


    public void showMain()
    {
    JPanel jp = new JPanel();
    jp.setLayout(new BorderLayout());
    
    showDiag = new JTextArea(20,50);
    showDiag.setEditable(false);
    putDiag = new JTextField();

    putDiag.addActionListener(new tfListener());
    
    jp.add(showDiag,BorderLayout.NORTH);
    jp.add(putDiag, BorderLayout.SOUTH);
    
    Container containerPane = getContentPane();
    containerPane.add(jp);

    setVisible(true); 


 
    while(true)
     recieveData();
    }
    

    
    private class tfListener implements ActionListener
    {
    public void actionPerformed(ActionEvent e)
    {
     String str = putDiag.getText().trim();
     sendData(str);
     stb.append("我说:"+str+" ");
     showDiag.setText(stb.toString());
     putDiag.setText("");
    }
    }
    
    
    public void sendData(String str)
    {
    byte[] dataArray = new byte[1000];
    dataArray = str.getBytes();
    try
    {
     InetAddress ia = InetAddress.getLocalHost();
    
     DatagramSocket ds = new DatagramSocket(8880);
     DatagramPacket dp = new DatagramPacket(dataArray,dataArray.length,ia,8888);
     ds.send(dp); //从自方8880端口发送到对方8888端口
     ds.close();
    } catch (SocketException e)
    {
     e.printStackTrace();
    } catch (IOException e)
    {
     e.printStackTrace();
    }
    }
    
    public void recieveData()
    {
    byte[] dataArray = new byte[1000];
    try
    {
     DatagramSocket ds = new DatagramSocket(8881);
     DatagramPacket dp = new DatagramPacket(dataArray,dataArray.length);  
     ds.receive(dp); //接受从自方8881端口接受来的数据
     stb.append(new String(dataArray).trim()+" ");      showDiag.setText(stb.toString());      ds.close();     } catch (SocketException e)     {      e.printStackTrace();     } catch (IOException e)     {      e.printStackTrace();     }         }          public static void main(String[] args)     {     UdpChatClient ucc = new UdpChatClient();     ucc.showMain();        } }

基于UDP的SOCKET编程，简单的说就是把数据写进PACKET，然后把PACKET通过指定的SOCKET传输到接收端的SOCKET，接收端拿到传过来PACKET，放进数组进行操作。

我这里的程序的服务器端和客户端都是基于一台电脑，如果要在多台电脑上测试把recieveData里的InetAddress不要用getLocalHost(),改为其它电脑的IP就可以了。