public class User{ /**  * 用戶信息類  * 用于記錄用戶個人信息:姓名以及IP  */ private String name; private String ip; public User(String name, String ip) {  this.name = name;  this.ip = ip; } public String getName() {  return name; } public void setName(String name) {  this.name = name; } public String getIp() {  return ip; } public void setIp(String ip) {  this.ip = ip; }}

import java.awt.BorderLayout;import java.awt.Color;import java.awt.GridLayout;import java.awt.Toolkit;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.io.PrintWriter;import java.net.BindException;import java.net.ServerSocket;import java.net.Socket;import java.util.ArrayList;import java.util.StringTokenizer;import javax.swing.DefaultListModel;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JList;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JSplitPane;import javax.swing.JTextArea;import javax.swing.JTextField;import javax.swing.border.TitledBorder;public class Server_more { private JFrame frame; private JTextArea contentArea; //文本域 private JTextField txt_message; //用于顯示文本信息 private JTextField txt_max;  //設置最大連接人數 private JTextField txt_port; //設置端口號 private JButton btn_start;  //開始按鈕 private JButton btn_stop;  //斷開按鈕 private JButton btn_send;  //發送按鈕 private JPanel northPanel;  //北方面板 private JPanel southPanel;  //南方面板 private JScrollPane rightPanel; //左邊滾動條 private JScrollPane leftPanel; //右邊滾動條 private JSplitPane centerSplit; //分割線 private JList userList;   //列表組件 private DefaultListModel listModel; private ServerSocket serverSocket; private ServerThread serverThread; private ArrayList<ClientThread> clients; private boolean isStart = false; // 主方法,程序執行入口 public static void main(String[] args) {  new Server_more(); } // 執行消息發送 public void send() {  if (!isStart) {   JOptionPane.showMessageDialog(frame, "服務器還未啟動,不能發送消息！", "錯誤",     JOptionPane.ERROR_MESSAGE);   return;  }  if (clients.size() == 0) {   JOptionPane.showMessageDialog(frame, "沒有用戶在線,不能發送消息！", "錯誤",     JOptionPane.ERROR_MESSAGE);   return;  }  String message = txt_message.getText().trim();  if (message == null || message.equals("")) {   JOptionPane.showMessageDialog(frame, "消息不能為空！", "錯誤",     JOptionPane.ERROR_MESSAGE);   return;  }  sendServerMessage(message);// 群發服務器消息  contentArea.append("服務器：" + txt_message.getText() + "/r/n");  txt_message.setText(null); } // 構造放法 public Server_more() {  frame = new JFrame("服務器");  // 更改JFrame的圖標：  //frame.setIconImage(Toolkit.getDefaultToolkit().createImage(Client.class.getResource("qq.png")));  //frame.setIconImage(Toolkit.getDefaultToolkit().createImage(Server.class.getResource("qq.png")));  contentArea = new JTextArea();  contentArea.setEditable(false);  contentArea.setForeground(Color.blue);  txt_message = new JTextField();  txt_max = new JTextField("30");  txt_port = new JTextField("6666");  btn_start = new JButton("啟動");  btn_stop = new JButton("停止");  btn_send = new JButton("發送");  btn_stop.setEnabled(false);  listModel = new DefaultListModel();  userList = new JList(listModel);  southPanel = new JPanel(new BorderLayout());  southPanel.setBorder(new TitledBorder("寫消息"));  southPanel.add(txt_message, "Center");  southPanel.add(btn_send, "East");  leftPanel = new JScrollPane(userList);  leftPanel.setBorder(new TitledBorder("在線用戶"));  rightPanel = new JScrollPane(contentArea);  rightPanel.setBorder(new TitledBorder("消息顯示區"));  centerSplit = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, leftPanel,    rightPanel);  centerSplit.setDividerLocation(100);  northPanel = new JPanel();  northPanel.setLayout(new GridLayout(1, 6));  northPanel.add(new JLabel("人數上限"));  northPanel.add(txt_max);  northPanel.add(new JLabel("端口"));  northPanel.add(txt_port);  northPanel.add(btn_start);  northPanel.add(btn_stop);  northPanel.setBorder(new TitledBorder("配置信息"));  frame.setLayout(new BorderLayout());  frame.add(northPanel, "North");  frame.add(centerSplit, "Center");  frame.add(southPanel, "South");  frame.setSize(600, 400);  //frame.setSize(Toolkit.getDefaultToolkit().getScreenSize());//設置全屏  int screen_width = Toolkit.getDefaultToolkit().getScreenSize().width;  int screen_height = Toolkit.getDefaultToolkit().getScreenSize().height;  frame.setLocation((screen_width - frame.getWidth()) / 2,    (screen_height - frame.getHeight()) / 2);  frame.setVisible(true);  // 關閉窗口時事件  frame.addWindowListener(new WindowAdapter() {   public void windowClosing(WindowEvent e) {    if (isStart) {     closeServer();// 關閉服務器    }    System.exit(0);// 退出程序   }  });  // 文本框按回車鍵時事件  txt_message.addActionListener(new ActionListener() {   public void actionPerformed(ActionEvent e) {    send();   }  });  // 單擊發送按鈕時事件  btn_send.addActionListener(new ActionListener() {   public void actionPerformed(ActionEvent arg0) {    send();   }  });  // 單擊啟動服務器按鈕時事件  btn_start.addActionListener(new ActionListener() {   public void actionPerformed(ActionEvent e) {    if (isStart) {     JOptionPane.showMessageDialog(frame, "服務器已處于啟動狀態，不要重復啟動！",       "錯誤", JOptionPane.ERROR_MESSAGE);     return;    }    int max;    int port;    try {     try {      max = Integer.parseInt(txt_max.getText());     } catch (Exception e1) {      throw new Exception("人數上限為正整數！");     }     if (max <= 0) {      throw new Exception("人數上限為正整數！");     }     try {      port = Integer.parseInt(txt_port.getText());     } catch (Exception e1) {      throw new Exception("端口號為正整數！");     }     if (port <= 0) {      throw new Exception("端口號 為正整數！");     }     serverStart(max, port);     contentArea.append("服務器已成功啟動!人數上限：" + max + ",端口：" + port       + "/r/n");     JOptionPane.showMessageDialog(frame, "服務器成功啟動!");     btn_start.setEnabled(false);     txt_max.setEnabled(false);     txt_port.setEnabled(false);     btn_stop.setEnabled(true);    } catch (Exception exc) {     JOptionPane.showMessageDialog(frame, exc.getMessage(),       "錯誤", JOptionPane.ERROR_MESSAGE);    }   }  });  // 單擊停止服務器按鈕時事件  btn_stop.addActionListener(new ActionListener() {   public void actionPerformed(ActionEvent e) {    if (!isStart) {     JOptionPane.showMessageDialog(frame, "服務器還未啟動，無需停止！", "錯誤",       JOptionPane.ERROR_MESSAGE);     return;    }    try {     closeServer();     btn_start.setEnabled(true);     txt_max.setEnabled(true);     txt_port.setEnabled(true);     btn_stop.setEnabled(false);     contentArea.append("服務器成功停止!/r/n");     JOptionPane.showMessageDialog(frame, "服務器成功停止！");    } catch (Exception exc) {     JOptionPane.showMessageDialog(frame, "停止服務器發生異常！", "錯誤",       JOptionPane.ERROR_MESSAGE);    }   }  }); } // 啟動服務器 public void serverStart(int max, int port) throws java.net.BindException {  try {   clients = new ArrayList<ClientThread>();   serverSocket = new ServerSocket(port);   serverThread = new ServerThread(serverSocket, max);   serverThread.start();   isStart = true;  } catch (BindException e) {   isStart = false;   throw new BindException("端口號已被占用，請換一個！");  } catch (Exception e1) {   e1.printStackTrace();   isStart = false;   throw new BindException("啟動服務器異常！");  } } // 關閉服務器 @SuppressWarnings("deprecation") public void closeServer() {  try {   if (serverThread != null)    serverThread.stop();// 停止服務器線程   for (int i = clients.size() - 1; i >= 0; i--) {    // 給所有在線用戶發送關閉命令    clients.get(i).getWriter().println("CLOSE");    clients.get(i).getWriter().flush();    // 釋放資源    clients.get(i).stop();// 停止此條為客戶端服務的線程    clients.get(i).reader.close();    clients.get(i).writer.close();    clients.get(i).socket.close();    clients.remove(i);   }   if (serverSocket != null) {    serverSocket.close();// 關閉服務器端連接   }   listModel.removeAllElements();// 清空用戶列表   isStart = false;  } catch (IOException e) {   e.printStackTrace();   isStart = true;  } } // 群發服務器消息 public void sendServerMessage(String message) {  for (int i = clients.size() - 1; i >= 0; i--) {   clients.get(i).getWriter().println("服務器：" + message + "(多人發送)");   clients.get(i).getWriter().flush();  } } // 服務器線程 class ServerThread extends Thread {  private ServerSocket serverSocket;  private int max;// 人數上限  // 服務器線程的構造方法  public ServerThread(ServerSocket serverSocket, int max) {   this.serverSocket = serverSocket;   this.max = max;  }  public void run() {   while (true) {// 不停的等待客戶端的鏈接    try {     Socket socket = serverSocket.accept();     if (clients.size() == max) {// 如果已達人數上限      BufferedReader r = new BufferedReader(        new InputStreamReader(socket.getInputStream()));      PrintWriter w = new PrintWriter(socket        .getOutputStream());      // 接收客戶端的基本用戶信息      String inf = r.readLine();      StringTokenizer st = new StringTokenizer(inf, "@");      User user = new User(st.nextToken(), st.nextToken());      // 反饋連接成功信息      w.println("MAX@服務器：對不起，" + user.getName()        + user.getIp() + "，服務器在線人數已達上限，請稍后嘗試連接！");      w.flush();      // 釋放資源      r.close();      w.close();      socket.close();      continue;     }     ClientThread client = new ClientThread(socket);     client.start();// 開啟對此客戶端服務的線程     clients.add(client);     listModel.addElement(client.getUser().getName());// 更新在線列表     contentArea.append(client.getUser().getName()       + client.getUser().getIp() + "上線!/r/n");    } catch (IOException e) {     e.printStackTrace();    }   }  } } // 為一個客戶端服務的線程 class ClientThread extends Thread {  private Socket socket;  private BufferedReader reader;  private PrintWriter writer;  private User user;  public BufferedReader getReader() {   return reader;  }  public PrintWriter getWriter() {   return writer;  }  public User getUser() {   return user;  }  // 客戶端線程的構造方法  public ClientThread(Socket socket) {   try {    this.socket = socket;    reader = new BufferedReader(new InputStreamReader(socket      .getInputStream()));    writer = new PrintWriter(socket.getOutputStream());    // 接收客戶端的基本用戶信息    String inf = reader.readLine();    StringTokenizer st = new StringTokenizer(inf, "@");    user = new User(st.nextToken(), st.nextToken());    // 反饋連接成功信息    writer.println(user.getName() + user.getIp() + "與服務器連接成功!");    writer.flush();    // 反饋當前在線用戶信息    if (clients.size() > 0) {     String temp = "";     for (int i = clients.size() - 1; i >= 0; i--) {      temp += (clients.get(i).getUser().getName() + "/" + clients        .get(i).getUser().getIp())        + "@";     }     writer.println("USERLIST@" + clients.size() + "@" + temp);     writer.flush();    }    // 向所有在線用戶發送該用戶上線命令    for (int i = clients.size() - 1; i >= 0; i--) {     clients.get(i).getWriter().println(       "ADD@" + user.getName() + user.getIp());     clients.get(i).getWriter().flush();    }   } catch (IOException e) {    e.printStackTrace();   }  }  @SuppressWarnings("deprecation")  public void run() {// 不斷接收客戶端的消息，進行處理。   String message = null;   while (true) {    try {     message = reader.readLine();// 接收客戶端消息     if (message.equals("CLOSE"))// 下線命令     {      contentArea.append(this.getUser().getName()        + this.getUser().getIp() + "下線!/r/n");      // 斷開連接釋放資源      reader.close();      writer.close();      socket.close();      // 向所有在線用戶發送該用戶的下線命令      for (int i = clients.size() - 1; i >= 0; i--) {       clients.get(i).getWriter().println(         "DELETE@" + user.getName());       clients.get(i).getWriter().flush();      }      listModel.removeElement(user.getName());// 更新在線列表      // 刪除此條客戶端服務線程      for (int i = clients.size() - 1; i >= 0; i--) {       if (clients.get(i).getUser() == user) {        ClientThread temp = clients.get(i);        clients.remove(i);// 刪除此用戶的服務線程        temp.stop();// 停止這條服務線程        return;       }      }     } else {      dispatcherMessage(message);// 轉發消息     }    } catch (IOException e) {     e.printStackTrace();    }   }  }  // 轉發消息  public void dispatcherMessage(String message) {   StringTokenizer stringTokenizer = new StringTokenizer(message, "@");   String source = stringTokenizer.nextToken();   String owner = stringTokenizer.nextToken();   String content = stringTokenizer.nextToken();   message = source + "：" + content;   contentArea.append(message + "/r/n");   if (owner.equals("ALL")) {// 群發    for (int i = clients.size() - 1; i >= 0; i--) {     clients.get(i).getWriter().println(message + "(多人發送)");     clients.get(i).getWriter().flush();    }   }  } }}

import java.awt.BorderLayout;import java.awt.Color;import java.awt.GridLayout;import java.awt.Toolkit;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.io.PrintWriter;import java.net.Socket;import java.util.HashMap;import java.util.Map;import java.util.StringTokenizer;import javax.swing.DefaultListModel;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JList;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JSplitPane;import javax.swing.JTextArea;import javax.swing.JTextField;import javax.swing.border.TitledBorder;public class Client_more{ private JFrame frame; private JList userList; private JTextArea textArea; private JTextField textField; private JTextField txt_port; private JTextField txt_hostIp; private JTextField txt_name; private JButton btn_start; private JButton btn_stop; private JButton btn_send; private JPanel northPanel; private JPanel southPanel; private JScrollPane rightScroll; private JScrollPane leftScroll; private JSplitPane centerSplit; private DefaultListModel listModel; private boolean isConnected = false; private Socket socket; private PrintWriter writer; private BufferedReader reader; private MessageThread messageThread;// 負責接收消息的線程 private Map<String, User> onLineUsers = new HashMap<String, User>();// 所有在線用戶 // 主方法,程序入口 public static void main(String[] args) {  new Client_more(); } // 執行發送 public void send() {  if (!isConnected) {   JOptionPane.showMessageDialog(frame, "還沒有連接服務器，無法發送消息！", "錯誤",     JOptionPane.ERROR_MESSAGE);   return;  }  String message = textField.getText().trim();  if (message == null || message.equals("")) {   JOptionPane.showMessageDialog(frame, "消息不能為空！", "錯誤",     JOptionPane.ERROR_MESSAGE);   return;  }  sendMessage(frame.getTitle() + "@" + "ALL" + "@" + message);  textField.setText(null); } // 構造方法 public Client_more() {  textArea = new JTextArea();  textArea.setEditable(false);  textArea.setForeground(Color.blue);  textField = new JTextField();  txt_port = new JTextField("6666");  txt_hostIp = new JTextField("127.0.0.1");  txt_name = new JTextField("吳承潛");  btn_start = new JButton("連接");  btn_stop = new JButton("斷開");  btn_send = new JButton("發送");  listModel = new DefaultListModel();  userList = new JList(listModel);  northPanel = new JPanel();  northPanel.setLayout(new GridLayout(1, 7));  northPanel.add(new JLabel("端口"));  northPanel.add(txt_port);  northPanel.add(new JLabel("服務器IP"));  northPanel.add(txt_hostIp);  northPanel.add(new JLabel("姓名"));  northPanel.add(txt_name);  northPanel.add(btn_start);  northPanel.add(btn_stop);  northPanel.setBorder(new TitledBorder("連接信息"));  rightScroll = new JScrollPane(textArea);  rightScroll.setBorder(new TitledBorder("消息顯示區"));  leftScroll = new JScrollPane(userList);  leftScroll.setBorder(new TitledBorder("在線用戶"));  southPanel = new JPanel(new BorderLayout());  southPanel.add(textField, "Center");  southPanel.add(btn_send, "East");  southPanel.setBorder(new TitledBorder("寫消息"));  centerSplit = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, leftScroll,    rightScroll);  centerSplit.setDividerLocation(100);  frame = new JFrame("客戶機");  // 更改JFrame的圖標： // frame.setIconImage(Toolkit.getDefaultToolkit().createImage(Client.class.getResource("qq.png")));  frame.setLayout(new BorderLayout());  frame.add(northPanel, "North");  frame.add(centerSplit, "Center");  frame.add(southPanel, "South");  frame.setSize(600, 400);  int screen_width = Toolkit.getDefaultToolkit().getScreenSize().width;  int screen_height = Toolkit.getDefaultToolkit().getScreenSize().height;  frame.setLocation((screen_width - frame.getWidth()) / 2,    (screen_height - frame.getHeight()) / 2);  frame.setVisible(true);  // 寫消息的文本框中按回車鍵時事件  textField.addActionListener(new ActionListener() {   public void actionPerformed(ActionEvent arg0) {    send();   }  });  // 單擊發送按鈕時事件  btn_send.addActionListener(new ActionListener() {   public void actionPerformed(ActionEvent e) {    send();   }  });  // 單擊連接按鈕時事件  btn_start.addActionListener(new ActionListener() {   public void actionPerformed(ActionEvent e) {    int port;    if (isConnected) {     JOptionPane.showMessageDialog(frame, "已處于連接上狀態，不要重復連接!",       "錯誤", JOptionPane.ERROR_MESSAGE);     return;    }    try {     try {      port = Integer.parseInt(txt_port.getText().trim());     } catch (NumberFormatException e2) {      throw new Exception("端口號不符合要求!端口為整數!");     }     String hostIp = txt_hostIp.getText().trim();     String name = txt_name.getText().trim();     if (name.equals("") || hostIp.equals("")) {      throw new Exception("姓名、服務器IP不能為空!");     }     boolean flag = connectServer(port, hostIp, name);     if (flag == false) {      throw new Exception("與服務器連接失敗!");     }     frame.setTitle(name);     JOptionPane.showMessageDialog(frame, "成功連接!");    } catch (Exception exc) {     JOptionPane.showMessageDialog(frame, exc.getMessage(),       "錯誤", JOptionPane.ERROR_MESSAGE);    }   }  });  // 單擊斷開按鈕時事件  btn_stop.addActionListener(new ActionListener() {   public void actionPerformed(ActionEvent e) {    if (!isConnected) {     JOptionPane.showMessageDialog(frame, "已處于斷開狀態，不要重復斷開!",       "錯誤", JOptionPane.ERROR_MESSAGE);     return;    }    try {     boolean flag = closeConnection();// 斷開連接     if (flag == false) {      throw new Exception("斷開連接發生異常！");     }     JOptionPane.showMessageDialog(frame, "成功斷開!");    } catch (Exception exc) {     JOptionPane.showMessageDialog(frame, exc.getMessage(),       "錯誤", JOptionPane.ERROR_MESSAGE);    }   }  });  // 關閉窗口時事件  frame.addWindowListener(new WindowAdapter() {   public void windowClosing(WindowEvent e) {    if (isConnected) {     closeConnection();// 關閉連接    }    System.exit(0);// 退出程序   }  }); } /**  * 連接服務器  *   * @param port  * @param hostIp  * @param name  */ public boolean connectServer(int port, String hostIp, String name) {  // 連接服務器  try {   socket = new Socket(hostIp, port);// 根據端口號和服務器ip建立連接   writer = new PrintWriter(socket.getOutputStream());   reader = new BufferedReader(new InputStreamReader(socket     .getInputStream()));   // 發送客戶端用戶基本信息(用戶名和ip地址)   sendMessage(name + "@" + socket.getLocalAddress().toString());   // 開啟接收消息的線程   messageThread = new MessageThread(reader, textArea);   messageThread.start();   isConnected = true;// 已經連接上了   return true;  } catch (Exception e) {   textArea.append("與端口號為：" + port + " IP地址為：" + hostIp     + " 的服務器連接失敗!" + "/r/n");   isConnected = false;// 未連接上   return false;  } } /**  * 發送消息  *   * @param message  */ public void sendMessage(String message) {  writer.println(message);  writer.flush(); } /**  * 客戶端主動關閉連接  */ @SuppressWarnings("deprecation") public synchronized boolean closeConnection() {  try {   sendMessage("CLOSE");// 發送斷開連接命令給服務器   messageThread.stop();// 停止接受消息線程   // 釋放資源   if (reader != null) {    reader.close();   }   if (writer != null) {    writer.close();   }   if (socket != null) {    socket.close();   }   isConnected = false;   return true;  } catch (IOException e1) {   e1.printStackTrace();   isConnected = true;   return false;  } } // 不斷接收消息的線程 class MessageThread extends Thread {  private BufferedReader reader;  private JTextArea textArea;  // 接收消息線程的構造方法  public MessageThread(BufferedReader reader, JTextArea textArea) {   this.reader = reader;   this.textArea = textArea;  }  // 被動的關閉連接  public synchronized void closeCon() throws Exception {   // 清空用戶列表   listModel.removeAllElements();   // 被動的關閉連接釋放資源   if (reader != null) {    reader.close();   }   if (writer != null) {    writer.close();   }   if (socket != null) {    socket.close();   }   isConnected = false;// 修改狀態為斷開  }  public void run() {   String message = "";   while (true) {    try {     message = reader.readLine();     StringTokenizer stringTokenizer = new StringTokenizer(       message, "/@");     String command = stringTokenizer.nextToken();// 命令     if (command.equals("CLOSE"))// 服務器已關閉命令     {      textArea.append("服務器已關閉!/r/n");      closeCon();// 被動的關閉連接      return;// 結束線程     } else if (command.equals("ADD")) {// 有用戶上線更新在線列表      String username = "";      String userIp = "";      if ((username = stringTokenizer.nextToken()) != null        && (userIp = stringTokenizer.nextToken()) != null) {       User user = new User(username, userIp);       onLineUsers.put(username, user);       listModel.addElement(username);      }     } else if (command.equals("DELETE")) {// 有用戶下線更新在線列表      String username = stringTokenizer.nextToken();      User user = (User) onLineUsers.get(username);      onLineUsers.remove(user);      listModel.removeElement(username);     } else if (command.equals("USERLIST")) {// 加載在線用戶列表      int size = Integer        .parseInt(stringTokenizer.nextToken());      String username = null;      String userIp = null;      for (int i = 0; i < size; i++) {       username = stringTokenizer.nextToken();       userIp = stringTokenizer.nextToken();       User user = new User(username, userIp);       onLineUsers.put(username, user);       listModel.addElement(username);      }     } else if (command.equals("MAX")) {// 人數已達上限      textArea.append(stringTokenizer.nextToken()        + stringTokenizer.nextToken() + "/r/n");      closeCon();// 被動的關閉連接      JOptionPane.showMessageDialog(frame, "服務器緩沖區已滿！", "錯誤",        JOptionPane.ERROR_MESSAGE);      return;// 結束線程     } else {// 普通消息      textArea.append(message + "/r/n");     }    } catch (IOException e) {     e.printStackTrace();    } catch (Exception e) {     e.printStackTrace();    }   }  } }}