java 的聊天案例

客户端：

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;

public class ChatClient extends Frame
{
 Socket s = null;
 DataOutputStream dos = null;
 DataInputStream dis = null;
 private boolean bConnected = false;

 TextField tfTxt = new TextField();

 TextArea taContent = new TextArea();
 
 Thread tRecv = new Thread(new RecvThread());

 public static void main(String[] args)
 {
  new ChatClient().launchFrame();
 }

 public void launchFrame()
 {
  setLocation(400, 300);
  this.setSize(300, 300);
  add(tfTxt, BorderLayout.SOUTH);
  add(taContent, BorderLayout.NORTH);
  pack();
  /*this.addWindowListener(new WindowAdapter() {

   @Override
   public void windowClosing(WindowEvent arg0) {
    disconnect();
    System.exit(0);
   }
   
  });*/
  tfTxt.addActionListener(new TFListener());
  setVisible(true);
  connect();
  
  tRecv.start();
 }
 
 public void connect()
 {
  try
  {
   s = new Socket("127.0.0.1", 8888);
   dos = new DataOutputStream(s.getOutputStream());
   dis = new DataInputStream(s.getInputStream());
System.out.println("connected!");
   bConnected = true;
  }
  catch (UnknownHostException e)
  {
   e.printStackTrace();
  }
  catch (IOException e)
  {
   e.printStackTrace();
  }
  
 }
 
 public void disconnect()
 {
  try
  {
   dos.close();
   dis.close();
   s.close();
  }
  catch (IOException e)
  {
   e.printStackTrace();
  }
 }
 
 private class TFListener implements ActionListener
 {

  public void actionPerformed(ActionEvent e)
  {
   String str = tfTxt.getText().trim();
   tfTxt.setText("");
   
   try
   {
    dos.writeUTF(str);
    dos.flush();
   }
   catch (IOException e1)
   {
    e1.printStackTrace();
   }
   
  }
  
 }
 
 private class RecvThread implements Runnable
 {

  public void run()
  {
   try
   {
    while(bConnected)
    {
     String str = dis.readUTF();
     taContent.setText(s.getInetAddress()+taContent.getText() + str + '/n');
    }
   }
   catch (SocketException e)
   {
    System.out.println("退出了，bye!");
   }
   catch (EOFException e)
   {
    System.out.println("推出了，bye - bye!");
   }
   catch (IOException e)
   {
    e.printStackTrace();
   }
   
  }
  
 }
}
服务器端：

import java.io.*;
import java.net.*;
import java.util.*;

public class ChatServer {
 boolean started = false;
 ServerSocket ss = null; 
 List<Client> clients = new ArrayList<Client>(); 
 public static void main(String[] args)
 {
  new ChatServer().start();
 }
 public void start(){
  try
  {
   ss = new ServerSocket(8888);
   started = true;
  }
  catch (BindException e) {
   System.out.println("端口使用中....");
   System.out.println("请关掉相关程序并重新运行服务器！");
   System.exit(0);
  }
  catch (IOException e)
  {
   e.printStackTrace();
  }
  try {
   while(started)
   {
    Socket s = ss.accept();
    Client c = new Client(s);
    System.out.println("a client connected!");
    new Thread(c).start();
    clients.add(c);
   }
  }
  catch (IOException e)
  {
   e.printStackTrace();
  }
  finally
  {
   try
   {
    ss.close();
   }
   catch (IOException e)
   {
    e.printStackTrace();
   }
  }
 }
 
 class Client implements Runnable
 {
  private Socket s;
  private DataInputStream dis = null;
  private DataOutputStream dos = null;
  private boolean bConnected = false;
  
  public Client(Socket s)
  {
   this.s = s;
   try
   {
     dis = new DataInputStream(s.getInputStream());
     dos = new DataOutputStream(s.getOutputStream());
     bConnected = true;
   }
   catch(IOException e)
   {
    e.printStackTrace();
   }
  }
  
  public void send(String str)
  {
   try
   {
    dos.writeUTF(str);
   }
   catch (IOException e)
   {
    clients.remove(this);
    System.out.println("对方退出了！我从List里面去掉了！");
   }
  }
  
  public void run()
  {
   try
   {
    while(bConnected)
    {
     String str = dis.readUTF();
     System.out.println(str);
     for(int i=0; i<clients.size(); i++)
     {
      Client c = clients.get(i);
      c.send(str);
     }
    }
   }
   catch (EOFException e)
   {
    System.out.println("Client closed!");
   }
   catch (IOException e)
   {
    e.printStackTrace();
   }
   finally
   {
    try
    {
     if(dis != null) dis.close();
     if(dos != null) dos.close();
     if(s != null) 
     {
      s.close();
     }
     
    }
    catch (IOException e1)
    {
     e1.printStackTrace();
    }
    
    
   }
  }
  
 }
}