在线聊天系统雏形

Server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);
        //dis.close();
      }
    } catch (IOException e) {
      e.printStackTrace();
    } finally {
      try {
        ss.close();
      } catch (IOException e) {
        // TODO Auto-generated catch block
        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！");
        //e.printStackTrace();
      }
    }
    
    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);
//System.out.println(" a string send !");
          }
          /*
          for(Iterator<Client> it = clients.iterator(); it.hasNext(); ) {
            Client c = it.next();
            c.send(str);
          }
          */
          /*
          Iterator<Client> it = clients.iterator();
          while(it.hasNext()) {
            Client c = it.next();
            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();
            //s = null;
          }
            
        } catch (IOException e1) {
          e1.printStackTrace();
        }
        
        
      }
    }
    
  }
}

 

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();
  }
  
  /*
  try {
   bConnected = false;
   tRecv.join();
  } catch(InterruptedException e) {
   e.printStackTrace();
  } finally {
   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();
   //taContent.setText(str);
   tfTxt.setText("");
   
   try {
//System.out.println(s);
    dos.writeUTF(str);
    dos.flush();
    //dos.close();
   } catch (IOException e1) {
    e1.printStackTrace();
   }
   
  }
  
 }
 
 private class RecvThread implements Runnable {

  public void run() {
   try {
    while(bConnected) {
     String str = dis.readUTF();
     //System.out.println(str);
     taContent.setText(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();
   }
   
  }
  
 }
}