java - 连接到服务器时客户端窗口不会关闭

Question

我已经制作了服务器和客户端应用程序(单独的 jar 文件)服务器只能向客户端发送文件，而客户端只能接受服务器发送的任何文件。

我的问题是，为什么我的客户端应用程序窗口在服务器先关闭之前不会关闭(按下关闭按钮时)？

这是我的代码:

服务器端

public sServerUI() {
    super("Server : "+System.getenv("COMPUTERNAME")); // mendapatkan nama komputer
    initComponents();
}
public void startListener(){    
    Random randomGen = new Random();
    int myPort = randomGen.nextInt(9999);
    try{
        server = new ServerSocket(myPort);//Bebas portnya, tp nggk boleh sudah terpakai atau pakai random jg bisa
        btnListen.setEnabled(false);
        while(_key == null) {
            _key = JOptionPane.showInputDialog(this, "Input your Key : ", "Insert Key", JOptionPane.PLAIN_MESSAGE);
        }
        if(_key.equals("")) {
            _key = "Random";
            txtMessage.setText(txtMessage.getText()+"Invalid key inputted, key automatically set to '"+_key+"'\n");
        } else txtMessage.setText(txtMessage.getText()+"Key set to '"+_key+"'\n");
    } catch (IOException e) {//Kalau sudah terpakai muncul error
        JOptionPane.showMessageDialog(this, "Could not listen at " + myPort);
        //Gagal, keluarin info
    } finally{
        myPort = server.getLocalPort();
        lblPort.setText("Port: "+myPort);
        System.out.println("Port: "+myPort);
    }

    _acceptClient.start();
}
public void windowClosing(WindowEvent e){
    try {
        server.close();
        for (int i=0;i<_numberOfClient;i++){
            //socketIn[i].close();
            _socketOut[i].close();
        }
    } catch (IOException ex) {
        System.out.println("Error "+ex.getMessage());
    }
}

class Accepter extends Thread{
    @Override
    public void run(){
        while (true){
            try{
                client[_numberOfClient] = server.accept();
                _numberOfClient++;
                lblStatus.setText("Status: "+_numberOfClient+" client(s) connected");

                Handler handleClient = new Handler(_numberOfClient-1);
                handleClient.start();
            } catch (IOException e) {
                JOptionPane.showMessageDialog(null, "Accept failed: " + e.getMessage());
            }
        }
    }
}
class Handler extends Thread{
    private int arr;
    Handler(int ar){
        arr = ar;
        try{
            //socketIn[arr] = new BufferedReader(new InputStreamReader(client[arr].getInputStream()));
            _socketOut[arr] = new DataOutputStream(client[arr].getOutputStream());
        } catch (IOException e) {
            JOptionPane.showMessageDialog(null, "Read failed");
        }
    }
}
/**
 * This method is called from within the constructor to initialize the form.
 * WARNING: Do NOT modify this code. The content of this method is always
 * regenerated by the Form Editor.
 */
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    btnListen = new javax.swing.JButton();
    lblStatus = new javax.swing.JLabel();
    jScrollPane1 = new javax.swing.JScrollPane();
    txtMessage = new javax.swing.JTextArea();
    btnSend = new javax.swing.JButton();
    lblPort = new javax.swing.JLabel();
    fileBtn = new javax.swing.JButton();

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
    setAutoRequestFocus(false);
    setBackground(new java.awt.Color(255, 255, 255));
    setResizable(false);

    btnListen.setText("Start Listening");
    btnListen.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            btnListenActionPerformed(evt);
        }
    });

    lblStatus.setText("Status: no client connected");

    txtMessage.setEditable(false);
    txtMessage.setColumns(20);
    txtMessage.setRows(5);
    jScrollPane1.setViewportView(txtMessage);

    btnSend.setText("Send");
    btnSend.setEnabled(false);
    btnSend.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            btnSendActionPerformed(evt);
        }
    });

    lblPort.setText("Port: ");

    fileBtn.setText("Choose File");
    fileBtn.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            fileBtnActionPerformed(evt);
        }
    });

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(layout.createSequentialGroup()
                    .addComponent(btnListen)
                    .addGap(18, 18, 18)
                    .addComponent(lblStatus)
                    .addGap(0, 133, Short.MAX_VALUE))
                .addComponent(jScrollPane1)
                .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                    .addComponent(lblPort, javax.swing.GroupLayout.PREFERRED_SIZE, 209, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(btnSend))
                .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                    .addGap(0, 0, Short.MAX_VALUE)
                    .addComponent(fileBtn)))
            .addContainerGap())
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(btnListen)
                .addComponent(lblStatus))
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 227, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addGap(9, 9, 9)
            .addComponent(fileBtn)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(btnSend)
                .addComponent(lblPort))
            .addContainerGap(14, Short.MAX_VALUE))
    );

    pack();
}// </editor-fold>                        

private void btnListenActionPerformed(java.awt.event.ActionEvent evt) {                                          
    // TODO add your handling code here:
    startListener();
}
private void btnSendActionPerformed(java.awt.event.ActionEvent evt) {                                        
    // TODO add your handling code here:
    if(_numberOfClient > 0) {
        int packetIndex = 1;
        String ext = getExt(_filePath, '.');
        byte fileChunk[];

        int k = 0;
        int blockIndex = 0;
        sendHeader("start "+_binaryData.length+" "+ext+" ");
        txtMessage.setText(txtMessage.getText()+"Sending file ...\n");
        for(int i = 0; i < _binaryData.length; i++) {
            if(k >= Math.ceil((double)_binaryData.length/10.0) || i == _binaryData.length-1) {
                if(i == _binaryData.length-1) k++;
                fileChunk = new byte[k];
                for(int x = 0; x < k; x++) {
                    fileChunk[x] = _binaryData[blockIndex];
                    blockIndex++;
                }
                printByteArr("file chunk : ", fileChunk);
                sendHeader(packetIndex+" ");
                packetIndex++;
                sendData(rc4(_key, fileChunk));
                k = 0;
            }
            k++;
        }
        sendHeader("end");
        txtMessage.setText(txtMessage.getText()+"File Sent !\n\n");
    } else JOptionPane.showMessageDialog(this, "No Client Connected !", "Error", JOptionPane.ERROR_MESSAGE);
}                                       

private void fileBtnActionPerformed(java.awt.event.ActionEvent evt) {                                        
    // TODO add your handling code here:
    JFileChooser chooser = new JFileChooser();
    chooser.setCurrentDirectory(new File("d:/Kul/Smstr 6/Kripto n Steno/Stream Cipher/"));
    int returnVal = chooser.showOpenDialog(this);

    if(returnVal == JFileChooser.APPROVE_OPTION) {
        _filePath = chooser.getSelectedFile().getPath();
        try {
            _file = new File(_filePath);
            _fis = new FileInputStream(_file);
            _binaryData = new byte[(int)_file.length()];
            System.out.println("file size : "+(int)_file.length()+" byte(s)");
            System.out.print("Isi file : ");
            _fis.read(_binaryData);
            _fis.close();
            for(int i = 0; i < _binaryData.length; i ++) {
                System.out.print(_binaryData[i]+" ");
            }
            System.out.print("end of file\n");

            String stringBuatDitampilin = getExt(_filePath, (char)92);

            txtMessage.setText(txtMessage.getText() + "'" + stringBuatDitampilin + "' Loaded !\n");
            btnSend.setEnabled(true);
        } catch(java.io.IOException e) {
            JOptionPane.showMessageDialog(this, e.toString(), "IO Error", JOptionPane.ERROR_MESSAGE);
        }
    }
}                                       

/**
 * @param args the command line arguments
 */
public static void main(String args[]) {
    /* Set the Nimbus look and feel */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(sServerUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /* Create and display the form */
    java.awt.EventQueue.invokeLater(new Runnable() {
        @Override
        public void run() {
            new sServerUI().setVisible(true);
        }
    });
}

客户端

public sClientUI() {
    super("Client");
    initComponents();
}
public void listenSocket(){
//Create _socket connection
    try{
        _socket = new Socket(txtHost.getText(), Integer.parseInt(txtPort.getText()));
        _socketIn = new DataInputStream(_socket.getInputStream());
        txtMessage.setText(txtMessage.getText()+"Succesfully connected to "+txtHost.getText()+" !\n");
        while(_key == null) {
            _key = JOptionPane.showInputDialog(this, "Input your Key : ", "Insert Key", JOptionPane.PLAIN_MESSAGE);
        }
        if(_key.equals("")) {
            _key = "Random";
            txtMessage.setText(txtMessage.getText()+"Invalid key inputted, key automatically set to '"+_key+"'\n");
        } else txtMessage.setText(txtMessage.getText()+"Key set to '"+_key+"'\n");
        txtHost.setEditable(false);
        txtPort.setEditable(false);
        btnConnect.setEnabled(false);
        myListener = new Timer(250, readLine);
        myListener.start();
    } catch (UnknownHostException e) {
        JOptionPane.showMessageDialog(this, "Unknown host: "+e.getMessage(), "Unknown Hostname", JOptionPane.ERROR_MESSAGE);
    } catch  (IOException e) {
        JOptionPane.showMessageDialog(this, "Either your hostname is wrong, or you entered wrong port number\n"+e.getMessage(),"Input Error", JOptionPane.ERROR_MESSAGE);
    } catch (NumberFormatException e) {
        JOptionPane.showMessageDialog(this, e.getMessage(),"Invalid Port Number", JOptionPane.ERROR_MESSAGE);
    }
}

public void windowClosing(WindowEvent e){
    try {
        _socket.close();
        _socketIn.close();
    } catch (IOException ex) {
        System.out.println("Error "+ex.getMessage());
    }
}
ActionListener readLine = new ActionListener(){
    @Override
    public void actionPerformed(ActionEvent ae) {
        try{
            int mLen;
            byte tempReceiver[];
            String header;

            if((header = _socketIn.readUTF()) != null) {
                if(!_readingHeader) {
                    if(!header.equals("end")) {
                        mLen = _socketIn.readInt();
                        System.out.println("mLen : "+mLen);
                        tempReceiver = new byte[mLen];
                        _socketIn.readFully(tempReceiver, 0, mLen);
                        printByteArr("bytes : ", tempReceiver);
                        txtMessage.setText(txtMessage.getText()+"Packet-"+header+" received : "+convertToString(tempReceiver)+"\n");
                        processBinaryData(rc4(_key, tempReceiver)); 
                    } else {
                        _binaryIndex = 0;
                        txtMessage.setText(txtMessage.getText()+"All packets downloaded !\n");
                        try {
                            String namaBaru = "File Output";
                            try (FileOutputStream out = new FileOutputStream(namaBaru+"."+_fileExt)) {
                                out.write(_binaryData);
                            } // ga perlu di close, karena sudah pake try-with-resource. fungsi ini otomatis close file yang sudah di try
                            txtMessage.setText(txtMessage.getText()+namaBaru+"."+_fileExt+" has been created !"+"\n\n");
                        } catch(FileNotFoundException f) {
                            System.out.println("Error : " + f.getMessage());
                        } catch(IOException io) {
                            System.out.println("Error : " + io.getMessage());
                        }
                        printByteArr("Complete File : ", _binaryData);
                        System.out.println(header);
                        _readingHeader = true;
                    }
                } else {
                    processHeader(header);
                    System.out.println("header : "+header);
                    txtMessage.setText(txtMessage.getText()+"Receiving new file ...\n");
                    _readingHeader = false;
                }
            }
        } catch (IOException e) {
            System.out.println("Read failed");
        }
    }
};
/**
 * This method is called from within the constructor to initialize the form.
 * WARNING: Do NOT modify this code. The content of this method is always
 * regenerated by the Form Editor.
 */
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    jScrollPane1 = new javax.swing.JScrollPane();
    txtMessage = new javax.swing.JTextArea();
    jLabel2 = new javax.swing.JLabel();
    txtHost = new javax.swing.JTextField();
    jLabel3 = new javax.swing.JLabel();
    txtPort = new javax.swing.JTextField();
    btnConnect = new javax.swing.JButton();

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
    setResizable(false);

    txtMessage.setEditable(false);
    txtMessage.setColumns(20);
    txtMessage.setRows(5);
    jScrollPane1.setViewportView(txtMessage);

    jLabel2.setText("Hostname: ");

    jLabel3.setText("Port: ");

    btnConnect.setText("Connect");
    btnConnect.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            btnConnectActionPerformed(evt);
        }
    });

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addComponent(jScrollPane1)
                .addGroup(layout.createSequentialGroup()
                    .addComponent(jLabel2)
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                    .addComponent(txtHost, javax.swing.GroupLayout.PREFERRED_SIZE, 126, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 23, Short.MAX_VALUE)
                    .addComponent(jLabel3)
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                    .addComponent(txtPort, javax.swing.GroupLayout.PREFERRED_SIZE, 111, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGroup(layout.createSequentialGroup()
                    .addComponent(btnConnect)
                    .addGap(0, 0, Short.MAX_VALUE)))
            .addContainerGap())
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(jLabel2)
                .addComponent(txtHost, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addComponent(jLabel3)
                .addComponent(txtPort, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(btnConnect)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 212, Short.MAX_VALUE)
            .addContainerGap())
    );

    pack();
}// </editor-fold>                
private void btnConnectActionPerformed(java.awt.event.ActionEvent evt) {                                           
    // TODO add your handling code here:
    listenSocket();
}                                          

/**
 * @param args the command line arguments
 */
public static void main(String args[]) {
    /* Set the Nimbus look and feel */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(sClientUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /* Create and display the form */
    java.awt.EventQueue.invokeLater(new Runnable() {
        @Override
        public void run() {
            new sClientUI().setVisible(true);
        }
    });
}

Answer 1

您必须在关闭客户端窗口之前关闭您的客户端套接字...