基于java編寫局域網(wǎng)多人聊天室
由于需要制作網(wǎng)絡計算機網(wǎng)絡課程設計,并且不想搞網(wǎng)絡布線或者局域網(wǎng)路由器配置等等這種完全搞不懂的東西,最后決定使用socket基于java編寫一個局域網(wǎng)聊天室:
關于socket以及網(wǎng)絡編程的相關知識詳見我另一篇文章:Java基于socket編程
程序基于C/S結構,即客戶端服務器模式。
服務器:
默認ip為本機ip
需要雙方確定一個端口號
可設置最大連接人數(shù)
可啟動與關閉
界面顯示在線用戶人以及姓名(本機不在此顯示)
客戶端:
需要手動設置服務器ip地址(局域網(wǎng))
手動設置端口號
輸入姓名
可連接可斷開
程序運行界面如下:
服務器:
客戶端:
具體代碼我會在最后上傳。
軟件有很多不足,其中比如:
沒有與數(shù)據(jù)庫有任何交集
優(yōu)化:可將所有用戶存放在數(shù)據(jù)庫中,以及將聊天記錄也放入數(shù)據(jù)庫中
沒有實現(xiàn)一對一聊天
優(yōu)化:需重新定義一對一聊天的方法
還有許多不足的地方,日后有興趣再回來慢慢研究
下面為該程序三個代碼:
User.java
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; } }
Server_more.java
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(shù) 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(fā)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(zhí)行入口 public static void main(String[] args) { new Server_more(); } // 執(zhí)行消息發(fā)送 public void send() { if (!isStart) { JOptionPane.showMessageDialog(frame, "服務器還未啟動,不能發(fā)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(fā)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(fā)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(fā)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(qū)")); 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(shù)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(fā)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(tài),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(shù)上限為正整數(shù)!"); } if (max <= 0) { throw new Exception("人數(shù)上限為正整數(shù)!"); } try { port = Integer.parseInt(txt_port.getText()); } catch (Exception e1) { throw new Exception("端口號為正整數(shù)!"); } if (port <= 0) { throw new Exception("端口號 為正整數(shù)!"); } serverStart(max, port); contentArea.append("服務器已成功啟動!人數(shù)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(fā)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(fā)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(fā)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(fā)送)"); clients.get(i).getWriter().flush(); } } // 服務器線程 class ServerThread extends Thread { private ServerSocket serverSocket; private int max;// 人數(shù)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(shù)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(shù)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(fā)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(fā)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(fā)消息 } } catch (IOException e) { e.printStackTrace(); } } } // 轉發(fā)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(fā) for (int i = clients.size() - 1; i >= 0; i--) { clients.get(i).getWriter().println(message + "(多人發(fā)送)"); clients.get(i).getWriter().flush(); } } } } }
Client_more.java
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(zhí)行發(fā)送 public void send() { if (!isConnected) { JOptionPane.showMessageDialog(frame, "還沒有連接服務器,無法發(fā)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(fā)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(qū)")); 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(fā)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(tài),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(shù)!"); } 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(tài),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(fā)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(jù)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(fā)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(jīng)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(fā)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(fā)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(tài)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(shù)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(qū)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(); } } } } }
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