package chat; import java.awt.BorderLayout;//布置容器的邊框布局import java.awt.Color;import java.awt.Container;import java.awt.GridLayout;//布局處理器import java.awt.Toolkit;//抽象超類import java.awt.event.ActionEvent;//指示發生了組件定義的動作的語義事件import java.awt.event.ActionListener;//用于接收操作事件的偵聽器接口import java.awt.event.MouseEvent;//指示組件中發生鼠標動作的事件import java.awt.event.MouseListener;//鼠標事件的偵聽器接口import java.awt.event.WindowAdapter;//接收窗口事件的抽象適配器類。此類中的方法為空。此類存在的目的是方便創建偵聽器對象import java.awt.event.WindowEvent;//指示窗口狀態改變的低級別事件import java.io.BufferedReader;//提供通用的緩沖方式文本讀取import java.io.IOException;//輸入輸出異常import java.io.InputStreamReader;//字節流通向字符流的橋梁import java.io.PrintWriter;//向文本輸出流打印對象的格式化表示形式import java.net.Socket;//套接字，網絡上的兩個程序通過一個雙向的通信連接實現數據交換的通信import java.util.HashMap;// HashMap 是 Map 接口的常用實現類import java.util.Map;//存數據，將鍵映射到值的對象import java.util.StringTokenizer;//允許應用程序將字符串分解為標記 import javax.swing.BorderFactory;//創建一個浮雕式的邊框import javax.swing.DefaultListModel;//列表模型import javax.swing.JButton;//按鈕import javax.swing.JFrame;//窗口import javax.swing.JLabel;//標簽import javax.swing.JList;//列表import javax.swing.JOptionPane;//對話框import javax.swing.JPanel;import javax.swing.JScrollPane;//視圖import javax.swing.JSplitPane;//分隔import javax.swing.JTextArea;//多行文本import javax.swing.JTextField;//文本import javax.swing.border.EmptyBorder;//一個占用空間但不執行繪制的空透明邊框import javax.swing.border.TitledBorder;//該類實現在指定位置以指定對齊方式顯示字符串標題的任意邊框 import oldchat.ChatFrame;  public class Client{  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;//創建套接字 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(); }  // 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()  { textArea = new JTextArea(); textArea.setEditable(false); textArea.setForeground(Color.blue); textField = new JTextField(); txt_port = new JTextField("6666"); txt_hostIp = new JTextField(); txt_name = new JTextField(); 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("群聊消息顯示區")); leftScroll = new JScrollPane(userList); leftScroll.setBorder(new TitledBorder("在線用戶(雙擊私聊)")); 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("客戶端"); // 更改JFrame的圖標： //frame.setIconImage(Toolkit.getDefaultToolkit().createImage(Client.class.getResource("qq.jpg"))); 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);  }  } });//雙擊聊天（私聊）  userList.addMouseListener(new MouseListener()  {    public void mouseReleased(MouseEvent e) {}  public void mousePressed(MouseEvent e) {}  public void mouseExited(MouseEvent e) {}  public void mouseEntered(MouseEvent e) {}  public void mouseClicked(MouseEvent e)   {  if(e.getClickCount()==2)   {   User user=onLineUsers.get(userList.getSelectedValue());    ChatFrame.main(user.getIp());;  }   } });  // 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();  }  } } } }

package chat; 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 {  private JFrame frame; private JTextArea contentArea; private JTextField txt_message; private JTextField txt_max; private JTextField txt_port; private JButton btn_start; private JButton btn_stop; private JButton btn_send; private JPanel northPanel; private JPanel southPanel; private JScrollPane rightPanel; private JScrollPane leftPanel; private JSplitPane centerSplit; private JList userList; 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(); }  // 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("服務器說：" + txt_message.getText() + "/r/n"); txt_message.setText(null); }  // 構造放法 public Server()  { 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.jpg"))); 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("群聊消息顯示區"));  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);  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 + "說：" + 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);   clients.get(i).getWriter().flush();  }  } } }}