一个简单的Java聊天室,帮我看看那里出错了.

Question

Register.java文件代码
import java.io.*;
import java.net.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
import java.util.*;
public class Register extends JFrame implements ActionListener
{
  //声明组件
  JLabel lblHeading;
  JLabel lblUserName;
  JLabel lblUserPwd;
  JLabel lblCnfUserPwd;
  JLabel lblFrstName;
  JLabel lblLstName;
  JLabel lblAge;
  JLabel lblEmpId;
  JLabel lblSex;  String usrName;
  char[] usrPwd;
  char[] cnfPwd;
  String frstName;
  String lstName;
  String age;
  String empid;  Socket toServer;
  ObjectInputStream streamFromServer;
  PrintStream streamToServer;
  JComboBox lstSex;  JTextField txtUserName;
  JPasswordField txtUsrPwd;
  JPasswordField txtCnfUsrPwd;
  JTextField txtFrstName;
  JTextField txtLstName;
  JTextField txtAge;
  JTextField txtEmpId;
  Font f; Color r;
  JButton btnSubmit;
  JButton btnCancel;  public Register()
  {
    this.setTitle("注册界面");
    JPanel panel=new JPanel();
  
    //应用布局管理器
    panel.setLayout(new GridBagLayout());
    GridBagConstraints gbCons=new GridBagConstraints();
    //放置图形组件
    gbCons.gridx=0;
    gbCons.gridy=0;
    lblHeading=new JLabel("注册信息");
    Font f=new Font("Monospaced", Font.BOLD, 24);
    lblHeading.setFont(f);
    Color c=new Color(0,200,0);
    lblHeading.setForeground(new Color(131,25,38));
    lblHeading.setVerticalAlignment(SwingConstants.TOP);
    gbCons.anchor=GridBagConstraints.WEST;
    panel.add(lblHeading, gbCons);    gbCons.gridx=0;
    gbCons.gridy=1;
    lblUserName=new JLabel("用户名称: ");
    gbCons.anchor=GridBagConstraints.WEST;
    panel.add(lblUserName, gbCons);    gbCons.gridx=1;
    gbCons.gridy=1;
    txtUserName=new JTextField(15);
    panel.add(txtUserName, gbCons);    gbCons.gridx=0;
    gbCons.gridy=2;
    lblUserPwd=new JLabel("密码: ");
    panel.add(lblUserPwd, gbCons);    gbCons.gridx=1;
    gbCons.gridy=2;
    txtUsrPwd=new JPasswordField(15);
    panel.add(txtUsrPwd, gbCons);    gbCons.gridx=0;
    gbCons.gridy=3;
    lblCnfUserPwd=new JLabel("确认密码: ");
    panel.add(lblCnfUserPwd, gbCons);    gbCons.gridx=1;
    gbCons.gridy=3;
    txtCnfUsrPwd=new JPasswordField(15);
    panel.add(txtCnfUsrPwd, gbCons);
  
    gbCons.gridx=0;
    gbCons.gridy=4;
    lblEmpId=new JLabel("雇员编号: ");
    panel.add(lblEmpId, gbCons);    gbCons.gridx=1;
    gbCons.gridy=4;
    txtEmpId=new JTextField(15);
    panel.add(txtEmpId, gbCons);    gbCons.gridx=0;
    gbCons.gridy=5;
    lblFrstName=new JLabel("名: ");
    panel.add(lblFrstName, gbCons);    gbCons.gridx=1;
    gbCons.gridy=5;
    txtFrstName=new JTextField(15);
    panel.add(txtFrstName, gbCons);    gbCons.gridx=0;
    gbCons.gridy=6;
    lblLstName=new JLabel("姓: ");
    panel.add(lblLstName, gbCons);    gbCons.gridx=1;
    gbCons.gridy=6;
    txtLstName=new JTextField(15);
    panel.add(txtLstName, gbCons);
  
    gbCons.gridx=0;
    gbCons.gridy=7;
    lblAge=new JLabel("年龄: ");
    panel.add(lblAge, gbCons);
  
    gbCons.gridx=1;
    gbCons.gridy=7;
    txtAge=new JTextField(3);
    panel.add(txtAge, gbCons);    gbCons.gridx=0;
    gbCons.gridy=8;
    lblSex=new JLabel("性别: ");
    panel.add(lblSex, gbCons);    gbCons.gridx=1;
    gbCons.gridy=8;
    String[] sex= {"男", "女"};
    JComboBox lstSex=new JComboBox(sex);
    lstSex.setSelectedIndex(0);
    panel.add(lstSex, gbCons);
    JPanel btnPanel=new JPanel();
  
    btnSubmit=new JButton("提交");
    btnPanel.add(btnSubmit);
    btnSubmit.addActionListener(this);
    //向"提交"按钮添加事件监听器
    btnCancel=new JButton("取消");
    btnPanel.add(btnCancel);
    btnCancel.addActionListener(this);
    //向"取消"按钮添加事件监听器
  
    gbCons.gridx=0;
    gbCons.gridy=9;
    gbCons.anchor=GridBagConstraints.EAST;
    panel.add(btnPanel, gbCons);
  
    getContentPane().add(panel);    setDefaultCloseOperation(EXIT_ON_CLOSE);    setVisible(true);
    setSize(450,400);
  }//Register()结束  public void actionPerformed(ActionEvent e1)
  {
     JButton button=(JButton)e1.getSource();
     //获取事件源
     if(button.equals(btnCancel))
     {
        this.dispose();
     }
     else
     {
        int ver=verify();  //调用verify()方法
        if(ver==1)
        {
           try
           {
             //建立一个Socket连接并创建一个Socket的输入输出流
             toServer = new Socket("wilson",1001);
             streamFromServer = new ObjectInputStream(toServer.getInputStream());
             streamToServer = new PrintStream(toServer.getOutputStream());             //向服务器发送消息进行注册
             streamToServer.println("注册信息");
             usrName = txtUserName.getText();
             usrPwd = txtUsrPwd.getPassword();
             String pwd = new String(usrPwd);
             //向服务器发送用户名和密码
             streamToServer.println(usrName+":"+pwd);
             //读取服务器的响应信息
             String frmServer = (String)streamFromServer.readObject();
             if(frmServer.equals("已注册"))
             {
                 new Login();
                 this.dispose();
             }
             else if(frmServer.equals("用户已存在"))
             {
                 showUsrExists();
                 //显示错误信息
             }
           }// try块结束
           catch(Exception e)
           {
              System.out.println("异常 "+e);
           } 
        }//if 块结束
     }//else 块结束
  }//actionPerformed()函数结束  int verify()  //检验用户信息的正确性
  {
     int ctr=0;
     int intAge = 0;
     try
     {
       usrName = txtUserName.getText();
       usrPwd = txtUsrPwd.getPassword();
       cnfPwd = txtCnfUsrPwd.getPassword();
       frstName = txtFrstName.getText();
       lstName = txtLstName.getText();
       age = txtAge.getText();
       empid = txtEmpId.getText();
       String strUsrPwd = new String(usrPwd);
       String strCnfPwd = new String(cnfPwd);
       try
       {
           intAge = (int)Integer.parseInt(age.trim());
       } 
       catch(Exception e)
       {
           showErrordlgInt();
       } 
       if(
            (usrName.length()>0)&&
            (strUsrPwd.length()>0)&&
            (strCnfPwd.length()>0)&&
            (frstName.length()>0)&&
            (lstName.length()>0)&&
            (intAge>21)&&
            (intAge<58)&&
            (empid.length()>0)&&
            (strUsrPwd.equals(strCnfPwd))  
       )
         {
             ctr = 1;
             return ctr;
         }
         else
         {
             showErrordlg();
         }// else 块结束
     }// try 块结束
     catch(Exception e)
     {
        System.out.println("抛出异常 "+e);
     }// catch 块结束
   return ctr;
  }// verify()函数结束  //错误信息---用户已存在
  void showUsrExists()
  {
      JOptionPane.showMessageDialog(
          this,
          "用户已存在.",
          "错误",
          JOptionPane.ERROR_MESSAGE);
  }  int flg = 0;  //错误信息---非法输入
  void showErrordlg()
  {
     JOptionPane.showMessageDialog(
         this,
         "非法输入.",
         "错误",
         JOptionPane.ERROR_MESSAGE);
  }  //错误信息---非法年龄
  void showErrordlgInt()
  {
     JOptionPane.showMessageDialog(
         this,
         "年龄不正确.",
         "错误",
         JOptionPane.ERROR_MESSAGE);
  }  public static void main(String args[])
  {
     new Register();
  }}//end of class

Answer 1

clientInt.java文件代码
import java.io.*;
import java.net.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
import java.util.*;
import javax.swing.Timer;public class clientInt extends JFrame implements ActionListener
{
   Timer t=new Timer(5000,new TimerAction());
   String usr_name;
   public String remUser;
   class TimerAction implements ActionListener
   {
      Socket toServer;
      ObjectInputStream streamFromServer;
      PrintStream streamToServer;
      public void actionPerformed(ActionEvent e2)
      {
         try
         {
            toServer = new Socket("wilson",1001);
            streamFromServer = new ObjectInputStream(toServer.getInputStream());
            streamToServer = new PrintStream(toServer.getOutputStream());
            message = txtMsg.getText();
            
            //send a message to the server
            streamToServer.println("From Timer");            //receive vectors from the server
            Vector vector = (Vector)streamFromServer.readObject();
            Vector vector1 = (Vector)streamFromServer.readObject();
            
            txtListUsers.setText(" ");
            for(int j = 1;j<vector1.capacity(); j++)
            {
               txtListUsers.append((String)vector1.elementAt(j));
               txtListUsers.append("\n");
            }
             
             //show the messages
             int i = messageCount;
            for(;i<vector.capacity();i++)
            {
               txtMessages.append((String)vector.elementAt(i));
               txtMessages.append("\n");
            }
             messageCount = i;
         }//end of try         catch(Exception e)
         {
            System.out.println("Exception "+e);
         }
      }//end of actionPerformed
   }//end of TimerListener class   int messageCount = 0;
   String name;
   PrintStream streamToServer;
   ObjectInputStream streamFromServer;
   Socket toServer;
   JTextArea txtMessages;
   JTextArea txtListUsers;
   JTextField txtMsg;
   JButton msgSendBtn;
   JButton userLoginBtn;
   JButton userRegisterBtn;
   JButton userLogoutBtn;   JLabel lblChatRoom;
   JLabel lblUserList;   JScrollPane jspSendMsgPane;
   JScrollPane jspTxtMsgPane;
   JScrollPane jspUserListPane;   JTextField textWriteMsg;
   String message;
   int nSend;

Answer 2

续上面的clientInt文件 public clientInt(String nm)
   {
      remUser = nm;
      usr_name = nm;
      this.setTitle("FunChat: "+usr_name); //set the title name
      JPanel panel = new JPanel();
      panel.setLayout(new GridBagLayout());
      GridBagConstraints gbCons = new GridBagConstraints();
  
      gbCons.gridx = 0;
      gbCons.gridy = 0;
      lblChatRoom = new JLabel("Chat Room", SwingConstants.LEFT);
      panel.add(lblChatRoom, gbCons);      gbCons.gridx = 1;
      gbCons.gridy = 0;      lblUserList = new JLabel("Online Users", SwingConstants.LEFT);
      panel.add(lblUserList, gbCons);
   
      gbCons.gridx = 0;
      gbCons.gridy = 1;
      gbCons.gridwidth = 1;
      gbCons.gridheight = 1;
      gbCons.weightx = 1.0;
      gbCons.weighty = 1.0;
      txtMessages = new JTextArea(25,35);
      txtMessages.setEditable(false);
      jspTxtMsgPane = new JScrollPane(txtMessages,JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
      panel.add(jspTxtMsgPane, gbCons);
    
      gbCons.gridx = 1;
      gbCons.gridy = 1;
      gbCons.gridwidth = 1;
      gbCons.gridheight = 1;
      gbCons.weightx = 1.0;
      gbCons.weighty = 1.0;
      txtListUsers = new JTextArea(25,10);
      txtListUsers.setEditable(false);
      jspUserListPane = new JScrollPane(txtListUsers,JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
      panel.add(jspUserListPane, gbCons);
 
      gbCons.gridx = 0;
      gbCons.gridy = 2;
      gbCons.gridwidth = 1;
      gbCons.gridheight = 1;
      gbCons.weightx = 1.0;
      gbCons.weighty = 1.0;
      txtMsg = new JTextField(35);      jspSendMsgPane = new JScrollPane(txtMsg,JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
      panel.add(jspSendMsgPane, gbCons);
 
      gbCons.gridx = 1;
      gbCons.gridy = 2;
      gbCons.gridwidth = 1;
      gbCons.gridheight = 1;
      gbCons.weightx = 1.0;
      gbCons.weighty = 1.0;
      gbCons.anchor = GridBagConstraints.WEST;
      msgSendBtn = new JButton("Send");
      panel.add(msgSendBtn, gbCons);
     
      msgSendBtn.addActionListener(this);
      JPanel btnPanel = new JPanel();
      userLogoutBtn = new JButton("Logout"); 
      userLogoutBtn.addActionListener(this);      //add a listener to the window
         this.addWindowListener(
                       new WindowAdapter()
                           {
                           public void windowClosing(WindowEvent e1)
                                    {
                                         try
                                         {
                                             Socket toServer;
                                            ObjectInputStream streamFromServer;
                                            PrintStream streamToServer;
                                            toServer = new Socket("wilson",1001);
                                            streamToServer = new PrintStream(toServer.getOutputStream());
                                            streamToServer.println("User Logout");
                                            streamToServer.println(remUser);
                                         }//end of try
                                         catch(Exception e2)
                                         {
                                             System.out.println("Exception Occured: "+e2);
                                         }
                                    
                                     }
                           }
                    );
               
      btnPanel.add(userLogoutBtn);
      gbCons.gridx = 0;
      gbCons.gridy = 3;
      gbCons.gridwidth = 1;
      gbCons.gridheight = 1;
      gbCons.weightx = 1.0;
      gbCons.weighty = 1.0;
      gbCons.anchor = GridBagConstraints.EAST;
      gbCons.fill = GridBagConstraints.HORIZONTAL;
      panel.add(btnPanel, gbCons);
      getContentPane().add(panel);
      setDefaultCloseOperation(EXIT_ON_CLOSE);     
      setVisible(true);
      setSize(546,567);
      t.start();   
   }//end of clientInt()   public void actionPerformed(ActionEvent e1)
   {
       JButton button = (JButton)e1.getSource();
 
       //if logout button clicked
       if(button.equals(userLogoutBtn))
       {
            try
            {
                toServer = new Socket("wilson",1001);
                streamToServer = new PrintStream(toServer.getOutputStream());
           
                //send a msg to server for logging out
                streamToServer.println("User Logout");
                streamToServer.println(remUser);
            }
            catch(Exception e)
            {
                System.out.println("Exception Occured: "+e);
            }
            this.dispose();
       }
       //else if Send button is clicked
       else
       {
            int num1 = 0,num2 = 0,res = 0;
            String name = " ";
            try
            {
                toServer = new Socket("wilson",1001);
                streamFromServer = new ObjectInputStream(toServer.getInputStream());
                streamToServer = new PrintStream(toServer.getOutputStream());
                message = txtMsg.getText();
                String msg = message;                //send the username and msg typedto the server
                streamToServer.println(usr_name+":"+msg); 
                txtMsg.setText(" ");
      
                //read the reply from the server
                Vector vector = (Vector)streamFromServer.readObject();
                int i = messageCount;
                for(;i<vector.capacity();i++)
                {
                     txtMessages.append((String)vector.elementAt(i)); //display the messages
                     // txtMessages.append("\n");
                }//end of for
                messageCount = i;
            }//end of try
            catch(Exception e)
            {
                System.out.println("Exception Occurred: "+e);
            }            
       }//end of else   }//end of actionPerformed()   public static void main(String args[])
   {
       String nm = new String();
       clientInt CI = new clientInt(nm);
   }
}//end of class

Answer 3

代码太多了，看不下去，建议把你的问题说清除就可以了
聊天室是基于socket的编程，建议先了解下socket原理，这对你理解这些代码有帮助。
new Socket("wilson",1001); 它是通过1001端口创建一个对象。端口可以自己指定，只要不于其他端口冲突就可以了。那它的用户名和密码是怎么保存的？ java是基于对象的编程，你new一个对象之后，它就在内存中创建一个对象，对象中包含用户的信息。因此，用户名和密码只在运行期间有效。它是保存在内存中的

Answer 4

你得先启动服务端程序，开始侦听某个端口的连接（等待客户端启动线程连接），你这里侦听的是1001号端口。（客户端也必需要通过1001号端口才能与服务器端取得连接。到于toServer=new Socket("wilson",1001); wilson是我的电脑名,但是不明白1001这个端口号嘛,这个端口号是自行指定的（但好像最好在1024以上，以避免和其它系统用的端口冲突)。楼主最好查一下Java的API，有详细介绍：
Socketpublic Socket(String host, int port) throws UnknownHostException, IOException    创建一个流套接字并将其连接到指定主机上的指定端口号。    如果指定的主机为 null，则等效于指定与 InetAddress.getByName(null) 相同的地址。换句话话，等效于指定回送接口的地址。    如果应用程序已指定服务器套接字工厂，则调用该工厂的 createSocketImpl 方法来创建实际套接字实现。否则创建“普通”套接字。    如果有安全管理器，则使用主机地址和 port 作为参数调用其 checkConnect 方法。这可能会导致 SecurityException 异常。    参数：
        host - 主机名，或者为 null，表示回送地址。
        port - 端口号。 
    抛出：
        UnknownHostException - 如果无法确定主机的 IP 地址。 
        IOException - 如果创建套接字时发生 I/O 错误。 
        SecurityException - 如果安全管理器存在并且其 checkConnect 方法不允许进行该操作。它没有用到数据库,那它的用户名和密码是怎么保存的,保存在那里呢???
看你的程序，应该是存放在流中（Stream）了……

Answer 5

AppServer.java文件代码
//import classes
import java.io.*;
import java.net.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
import java.util.*;
import javax.swing.Timer.*;//Code for the AppServer classpublic class AppServer implements Runnable
{
   ServerSocket server;
   Socket fromClient;
   Thread serverThread;   public AppServer()
   {
      System.out.print("FunChat server started..........");
      try
      {
         server = new ServerSocket(1001);
         serverThread = new Thread(this);
         serverThread.start();
      }
      catch(Exception e)
      {
         System.out.println("Cannot start the thread: " + e);
      }
   }//end of AppServer()   public static void main(String args[])
   {
      new AppServer();
   }   public void run()
   {
      try
      {
         while(true)
         {
            //Listening to the clients request
            fromClient = server.accept();
            //Creating the connect object
            Connect con = new Connect(fromClient);
         }
      }
      catch(Exception e)
      {
         System.out.println("Cannot listen to the client: " + e);
      }
   }//end of run}//end of Appserver class//Code for the connect class
class Connect
{
  ObjectOutputStream streamToClient;
  int ctr = 0;  BufferedReader streamFromClient;
  static Vector vector;
  static Vector vctrList;
  String mesg = " ";
  static String str = new String("UsrList");
  
  static
  {
     vector = new Vector(1,1);
     vctrList = new Vector(1,1);
     vctrList.addElement((String)str);
  }  int verify(String mesg)
  {
     try
     {
        RandomAccessFile RAS = new RandomAccessFile("UsrPwd.txt", "r");
        int i = 0;
        String str = " ";
        while((RAS.getFilePointer())!=(RAS.length()))
        {
           str = RAS.readLine();
           if(str.equals(mesg))
           {
              ctr = 1;
              break;
           }
        } //end of while
        RAS.close();
     } //end of try
     catch(Exception e)
     {
        System.out.print("Exception Occurred: "+e);
     }
     return ctr;
  } //end of verify()  int checkFile(String mesg)
  {
     int chk = 1;
     try
     {
        RandomAccessFile RS = new RandomAccessFile("UsrPwd.txt", "r");
        int i = 0;
        String str = " ";
        String colon = new String(":");
        int index = ((String)mesg).lastIndexOf(colon);
        String userName = (String)mesg.substring(0,index);
        while((RS.getFilePointer())!=(int)(RS.length()))
        {
           str = RS.readLine();
           int index1 = ((String)str).lastIndexOf(colon);
           String usrName = (String)str.substring(0,index1);
           if(usrName.equals(userName))
           {
              chk = 0;
              break;
           }
        }//end of while
        RS.close();
     }//end of try
     catch(Exception e)
     {
        System.out.print("Exception Occurred: "+e);
     }  
     return chk;
  }//end of chkFile  public Connect(Socket inFromClient)
  {
     //Retrieving the clients stream
     String msg = " ";
     String message = " ";
     try
     {
        streamFromClient = new BufferedReader(new InputStreamReader(inFromClient.getInputStream()));
        streamToClient = new ObjectOutputStream(inFromClient.getOutputStream());        msg = streamFromClient.readLine();
        if((msg.equals("From Timer")))
        {
           streamToClient.writeObject(vector);
           streamToClient.writeObject(vctrList);
        }
        else if(msg.equals("LoginInfo"))
        {
           msg = streamFromClient.readLine();
           int ver = verify(msg);
           if(ver==1)
           {
               String colon = new String(":");
               int index = ((String)msg).lastIndexOf(colon);
               String userName = (String)msg.substring(0,index);
               if(!(vctrList.indexOf((String)userName)>0))
               {
                  streamToClient.writeObject("Welcome");
                  
                  vctrList.addElement((String)userName);
               }
           }
           else
           {
              streamToClient.writeObject("Login denied");
           }
        }
        else if(msg.equals("RegisterInfo"))
        {
           msg = streamFromClient.readLine();
           int ret = checkFile(msg);
           if(ret==0)
           {
              FileOutputStream out = new FileOutputStream("UsrPwd.txt",true);
              PrintStream p = new PrintStream(out);
              p.println();
              p.println(msg);
              p.close();
              streamToClient.writeObject("Registered");
           }
        }
        else if(msg.equals("User Logout"))
        {
           String remUser = streamFromClient.readLine();
           boolean b = vctrList.removeElement((String)remUser);
        } 
        else
        {
           message = message+msg;
           vector.addElement((String)message);
           streamToClient.writeObject(vector);
        }
     }//end of try
     catch(Exception e)
     {
        System.out.println("Cannot get the client stream connect" + e);
     }
     finally
     {
         try
         {
             inFromClient.close();
         }
         catch(IOException e)
         {
             System.out.print("Exception Occurred: "+e);
         }
     }
  
  }//end of Connect()
}