chatserver.java

一个简单的聊天

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


public class chatServer extends JFrame {
  //以下为图形界面变量
  JPanel contentPane;
  JMenuBar jMenuBar1 = new JMenuBar();
  JMenu jMenuFile = new JMenu();
  JMenuItem jMenuFileExit = new JMenuItem();
  JMenu jMenuHelp = new JMenu();
  JMenuItem jMenuHelpAbout = new JMenuItem();
  JLabel statusBar = new JLabel();
  BorderLayout borderLayout1 = new BorderLayout();
  JPanel jPanel1 = new JPanel();
  BorderLayout borderLayout2 = new BorderLayout();
  JLabel jLabel1 = new JLabel();
  static java.awt.List jList1 = new java.awt.List(13);
 
  JScrollPane scrollpane=new JScrollPane(jList1);
  
  
  //以下为网络相关变量
  static Vector clients=new Vector(10);   //用vector向量数组存储连接客户变量
  static ServerSocket server=null;        //建立服务器socket
  static int active_connects=0;           //用来存储目前连接的客户数
  static Socket socket=null;               //用来存储一个套接字连接
  


  //chatServer main method
   public static void main(String[] args) {
    try {
      UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
    }
    catch(Exception e) {
      e.printStackTrace();
    }
    chatServer chatServer1=new chatServer();      //实例化一个chatServer类
	chatServer1.show();
	System.out.println("Server starting ...");
	
	try
	   {
	    server=new ServerSocket(2525);      //使用端口2525初始化服务器套接字
	}
	catch(IOException e)
	   {
	    System.out.println("Error:"+e);
	}
	while(true)
	   {
	   
	    if(clients.size()<5)       //当客户数小于5个时开始连接
		   {
		    try
			   {
			    socket=server.accept();   //用来存储连接上的客户socket
			    if(socket!=null)
			    {
			    System.out.println(socket+"连接");    //在控制台打印客户连接信息
			    
			    
			 }
			}
			catch(IOException e)
			   {
			    System.out.println("Error:"+e);
			}
			int i=0;
			
			
			   do{
			    
			    Client c=new Client(socket);      //定义并实例化一个Client线程类，一个就对应一个客户连接
			    clients.addElement(c);             //加入clients数组中
				if(checkName(c))                  //调用checkName方法验证c的合法性
				   {
				    int connum=++chatServer1.active_connects;  //定义connum来存储活动连接数
				    String constr="目前有"+connum+"客户相连";    //在状态栏里显示连接数
				    chatServer1.statusBar.setText(constr);
				    Client listdata=(Client)clients.elementAt(i);   //将连接客户的socket信息存储进listdata数组
				    
				    chatServer1.jList1.addItem(listdata.ip+"连接",i);  //将客户socket信息写入list框
				    c.start();                                        //启动线程
					notifyRoom();                                    //用notifyRoom方法来监视聊天室连接变化
					                                                 //不断改变clients数组并刷新客户端信息
					
				}
				else
				   {
				    //如果名字不合法
				    c.ps.println("TAKEN");
				    
					disconnect(c);
					
				}
				i++;
				break;
				
			}
			while(i<clients.size());
			
		}
		else                                   //如果clients数组超过了5个
		   {
			try{Thread.sleep(200);}
			catch(InterruptedException e)
			   {
			}
		}
	}//end of while
  }// end of main method

  /**Construct the frame*/
  public chatServer()                          //chatServer类的构造器用来初始化一些UI信息
  {
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }
  /**Component initialization*/
  private void jbInit() throws Exception  {
    //setIconImage(Toolkit.getDefaultToolkit().createImage(Frame1.class.getResource("[Your Icon]")));
    contentPane = (JPanel) this.getContentPane();
    contentPane.setLayout(borderLayout1);
    this.setSize(new Dimension(400, 300));
    this.setTitle("简易聊天服务器端");
    statusBar.setText("目前的连接数为：");
    
    jMenuFile.setText("File");
    jMenuFileExit.setText("Exit");
    jMenuFileExit.addActionListener(new ActionListener()  {
      public void actionPerformed(ActionEvent e) {
        jMenuFileExit_actionPerformed(e);
      }
    });
    jMenuHelp.setText("Help");
    jMenuHelpAbout.setText("About");
    jMenuHelpAbout.addActionListener(new ActionListener()  {
      public void actionPerformed(ActionEvent e) {
        jMenuHelpAbout_actionPerformed(e);
      }
    });
    
    
    jPanel1.setLayout(borderLayout2);
    jLabel1.setText("服务器端连接客户");
    jMenuFile.add(jMenuFileExit);
    jMenuHelp.add(jMenuHelpAbout);
    jMenuBar1.add(jMenuFile);
    jMenuBar1.add(jMenuHelp);
    this.setJMenuBar(jMenuBar1);
    contentPane.add(statusBar, BorderLayout.SOUTH);
    contentPane.add(jPanel1, BorderLayout.CENTER);
    jPanel1.add(jLabel1,  BorderLayout.NORTH);
    jPanel1.add(scrollpane, BorderLayout.CENTER);

	
  }//end of jbinit
  /**File | Exit action performed*/
  public void jMenuFileExit_actionPerformed(ActionEvent e)   //实现退出菜单方法
{
    sendClients(new StringBuffer("QUIT"));                   //向客户端发送断开连接信息
	closeAll();                                               //调用closeAll方法关闭所有连接
	System.exit(0);
  }
  /**Help | About action performed*/
  public void jMenuHelpAbout_actionPerformed(ActionEvent e)  //实现about对话框，意义不大，可以去掉
  {
    chatServer_AboutBox dlg = new chatServer_AboutBox(this);
    Dimension dlgSize = dlg.getPreferredSize();
    Dimension frmSize = getSize();
    Point loc = getLocation();
    dlg.setLocation((frmSize.width - dlgSize.width) / 2 + loc.x, (frmSize.height - dlgSize.height) / 2 + loc.y);
    dlg.setModal(true);
    dlg.show();
  }                                
  /**Overridden so we can exit when window is closed*/
  protected void processWindowEvent(WindowEvent e)          //实现关闭服务器程序要进行的操作
	  {
    super.processWindowEvent(e);
    if (e.getID() == WindowEvent.WINDOW_CLOSING) {
      jMenuFileExit_actionPerformed(null);
    }
  }



  /*以下实现各种方法*/
  public static void notifyRoom()                          //用来监视连接信息，不断刷新clients数组并刷新客户端用户列表信息
	{
     StringBuffer people=new StringBuffer("PEOPLE");
	 for(int i=0;i<clients.size();i++)
		{
	     Client c=(Client)clients.elementAt(i);
		 people.append(":"+c.name);
		 
	 }
	 sendClients(people);                                 //用sendClients方法向客户端发送信息
  }

  public static synchronized void sendClients(StringBuffer msg)   //实现sendClients方法专用来向每个连接的客户端发送信息
	{
     for(int i=0;i<clients.size();i++)
		{
	     Client c=(Client)clients.elementAt(i);
		 c.send(msg);
	 }
  }

  public static void closeAll()                             //实现关闭所有连接信息
	{
     while(clients.size()>0)                                 //遍历clients数组删除所有连接客户信息
		{
	     Client c=(Client)clients.firstElement();
		 try
			{
		     c.socket.close();
		 }
		 catch(IOException e)
			{
		     System.out.println("Error:"+e);
		 }
		 finally
			{
		     clients.removeElement(c);
		 }
	 }//end of while
  }//end of closeAll method

  public static boolean checkName(Client newclient)         //实现检查连接客户的socket信息是否合法
	{
     for(int i=0;i<clients.size();i++)
		{
	     Client c=(Client)clients.elementAt(i);
		 if((c!=newclient)&&c.equals(newclient.name))
			 return false;
	 }
	 return(true);
  }//end of checkName method

  public static synchronized void disconnect(Client c)         //实现断开单个客户的方法
	{
     try
		{
		 jList1.addItem(c.ip+"断开连接");                      //在服务器端程序的list框中显示断开信息
		 
		 chatServer.active_connects--;                       //将连接数减1
	     c.send(new StringBuffer("QUIT"));                    //向客户发送断开连接信息
		 c.socket.close();
		 
	 }
	 catch(IOException e)
		{
	     System.out.println("Error:"+e);
	 }
	 finally
		{
	     clients.removeElement(c);                          //从clients数组中删除此客户的相关socket等信息
	 }
  }


}
class Client extends Thread                              //实现 Client线程类
  {
    Socket socket;                                       //用来存储一个连接客户的socket信息
	String name;                                         //用来存储客户的连接姓名
	String ip;                                           //用来存储客户的ip信息
 	DataInputStream dis;                                 //用来实现接受从客户端发来的数据流
	PrintStream ps;                                      //用来实现向客户端发送信息的打印流

	public void send(StringBuffer msg)                   //实现想客户端发送信息的方法
	  {
	   ps.println(msg);                                  //用打印流发送信息
	   ps.flush();
	}

	public  Client(Socket s)                             //Client线程类的构造器
	  {
	   socket=s;                                           
	   try
		  {
	       dis=new DataInputStream(s.getInputStream());  //存储特定客户socket的输入流接受s这个客户发送到服务器端的信息
		   ps=new PrintStream(s.getOutputStream());      //存储特定客户socket的输出流发送服务器给s这个客户的信息
		   String info=dis.readLine();                   //读取接受来的信息
		   
		   StringTokenizer stinfo=new StringTokenizer(info,":");  //用StringTokenizer类来读取用"："分段字符
		   String head=stinfo.nextToken();                        //head用来存储类似于关键字的头信息
           if(stinfo.hasMoreTokens())		   
		   name=stinfo.nextToken();                               //关键字后的第二段数据是客户名信息
		   if(stinfo.hasMoreTokens())
		   ip=stinfo.nextToken();                                  //关键字后的第三段数据是客户ip信息
		   System.out.println(head);                               //在控制台打印头信息
	   }
	   catch(IOException e)
		  {
	       System.out.println("Error:"+e);
	   }
	}//end of Client constrator

	public void run()                                           //线程运行方法
	  {
	   while(true)
		  {
	       String line=null;
		   try
			  {
		       line=dis.readLine();                            //读取客户端发来的数据流
		       
		   }
		   catch(IOException e)
			  {
		       System.out.println("Error"+e);
			   chatServer.disconnect(this);
			   chatServer.notifyRoom();
			   return;
		   }

		   if(line==null)    //客户已离开
			  {
			   chatServer.disconnect(this);
			   chatServer.notifyRoom();
			   return;
			  }
		   
		   StringTokenizer st=new StringTokenizer(line,":");
		   String keyword=st.nextToken();

		   if(keyword.equals("MSG"))                          //如果关键字是MSG则是客户端发来的聊天信息
			  {
		       StringBuffer msg=new StringBuffer("MSG:");     //在服务器端再重新建立一个字符缓冲
			   msg.append(name);
			   msg.append(st.nextToken("\0"));
			   chatServer.sendClients(msg);                   //再将某个客户发来的聊天信息发送到每个连接客户的聊天栏中
		   }
		   else if(keyword.equals("QUIT"))                   //如果关键字是QUIT则是客户端发来断开连接的信息
			  {
		       
		       chatServer.disconnect(this);                  //服务器断开与这个客户的连接
			   chatServer.notifyRoom();                      //继续监听聊天室并刷新其他客户的聊天人名list
			   this.stop();                                   
		   }
	   }
	}
  }  //end of class Client