我知道确切的问题所在。当我在Steganography_Controller构造函数中调用FileTransfer方法时，窗口挂起。当我评论该方法调用时，代码工作正常。这是一个有效的代码。
这是我的Steganography_Controller类
public class Steganography_Controller {
// Program Variables
private Steganography_View view;
// Panel Displays
private JPanel decode_panel;
private JPanel encode_panel;
// Panel Variables
private JTextArea input;
private JButton encodeButton, decodeButton;
private JLabel image_input;
// Menu Variables
private JMenuItem encode;
private JMenuItem decode;
private JMenuItem sendfile;
private JMenuItem calculatepsnr;
private JMenuItem exit;
// action event classes
private Encode enc;
private Decode dec;
/*private SendFile send;
private CalculatePSNR psnr;*/
private EncodeButton encButton;
private DecodeButton decButton;
// decode variable
private String stat_path = "";
private String stat_name = "";
// encode variable
private String stegan = "";
private String path = "";
/*
* Constructor to initialize view, model and environment variables
*
* @param aView A GUI class, to be saved as view
*
* @param aModel A model class, to be saved as model
*/
public Steganography_Controller(Steganography_View aView) {
// program variables
view = aView;
//model = aModel;
// assign View Variables
// 2 views
encode_panel = view.getTextPanel();
decode_panel = view.getImagePanel();
// 2 data options
input = view.getText();
image_input = view.getImageInput();
// 2 buttons
encodeButton = view.getEButton();
decodeButton = view.getDButton();
// menu
encode = view.getEncode();
decode = view.getDecode();
sendfile = view.getSendFile();
calculatepsnr = view.getPSNR();
exit = view.getExit();
// assign action events
enc = new Encode();
encode.addActionListener(enc);
dec = new Decode();
decode.addActionListener(dec);
/*send = new SendFile();
sendfile.addActionListener(send);
psnr = new CalculatePSNR();
calculatepsnr.addActionListener(psnr);*/
exit.addActionListener(new Exit());
encButton = new EncodeButton();
encodeButton.addActionListener(encButton);
decButton = new DecodeButton();
decodeButton.addActionListener(decButton);
// encode view as default
encode_view();
FileTransfer(); /* <----- Here's what hangs the code.Maybe because i am using socket connection but would like to know the exact problem and solutions if any.*/
}
/*
* Updates the single panel to display the Encode View.
*/
private void encode_view() {
update();
view.setContentPane(encode_panel);
view.setVisible(true);
}
/*
* Updates the single panel to display the Decode View.
*/
private void decode_view() {
update();
view.setContentPane(decode_panel);
view.setVisible(true);
}
/*
* Encode Class - handles the Encode menu item
*/
private class Encode implements ActionListener {
/*
* handles the click event
*
* @param e The ActionEvent Object
*/
public void actionPerformed(ActionEvent e) {
encode_view(); // show the encode view
}
}
/*
* Decode Class - handles the Decode menu item
*/
private class Decode implements ActionListener {
/*
* handles the click event
*
* @param e The ActionEvent Object
*/
public void actionPerformed(ActionEvent e) {
decode_view(); // show the decode view
// start path of displayed File Chooser
}
}
/*
* Exit Class - handles the Exit menu item
*/
private class Exit implements ActionListener {
/*
* handles the click event
*
* @param e The ActionEvent Object
*/
public void actionPerformed(ActionEvent e) {
System.exit(0); // exit the program
}
}
/*
* Encode Button Class - handles the Encode Button item
*/
private class EncodeButton implements ActionListener {
/*
* handles the click event
*
* @param e The ActionEvent Object
*/
public void actionPerformed(ActionEvent e) {
}
}
/*
* Decode Button Class - handles the Decode Button item
*/
private class DecodeButton implements ActionListener {
/*
* handles the click event
*
* @param e The ActionEvent Object
*/
public void actionPerformed(ActionEvent e) {
}
}
/*
* Listens to incoming socket connections and receives file
*/
public void FileTransfer() {
try {
System.out.println("Server running...");
/* Listen on port 1111 */
ServerSocket server = new ServerSocket(1111);
/* Accept the sk */
while (true) {
Socket sk = server.accept();
System.out.println("Server accepted client");
InputStream input = sk.getInputStream();
BufferedReader inBuf = new BufferedReader(
new InputStreamReader(sk.getInputStream()));
BufferedWriter outBuf = new BufferedWriter(
new OutputStreamWriter(sk.getOutputStream()));
/* Read the filename */
String filename = inBuf.readLine();
if (!filename.equals("")) {
/* Reply back to client with READY status */
outBuf.write("READY\n");
outBuf.flush();
}
// System.out.println("\nfilename:"+filename);
/* Create a new file in the tmp directory using the filename */
String workingDir = System.getProperty("user.dir");
// System.out.println("Working Dir:"+workingDir);
String path = workingDir + "\\images\\" + filename;
System.out.println("serverpath:" + path);
int filesize = 2022386;
int bytesRead;
int currentTot = 0;
byte[] bytearray = new byte[filesize];
FileOutputStream fos = new FileOutputStream(new File(path));
BufferedOutputStream bos = new BufferedOutputStream(fos);
bytesRead = input.read(bytearray, 0, bytearray.length);
currentTot = bytesRead;
do {
bytesRead = input.read(bytearray, currentTot,
(bytearray.length - currentTot));
if (bytesRead >= 0)
currentTot += bytesRead;
} while (bytesRead > -1);
bos.write(bytearray, 0, currentTot);
// System.out.println("BYteRECEive:"+bytesReceived);
input.close();
fos.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
public void update() {
input.setText(""); // clear textarea
image_input.setIcon(null); // clear image
stat_path = ""; // clear path
stat_name = ""; // clear name
}
/*
* Main Method for testing
*/
/*public static void main(String args[]) {
new Steganography_Controller(new Steganography_View("Steganography"),
new Steganography());
}*/
}
这是登录类
public class Login extends JDialog {
private JTextField tfUsername;
private JPasswordField tfPassword;
private JLabel lbUsername;
private JLabel lbPassword;
private JButton btnLogin;
private JButton btnCancel;
private JButton btnRegister;
private boolean succeeded;
// Steganography_Controller controller;
final static JFrame frame = new JFrame("JDialog Demo");
public Login(Frame parent) {
super(parent, "Login", true);
JDialog dialog = new JDialog();
JPanel panel = new JPanel(new GridBagLayout());
GridBagConstraints cs = new GridBagConstraints();
cs.fill = GridBagConstraints.HORIZONTAL;
lbUsername = new JLabel("Username: ");
cs.gridx = 0;
cs.gridy = 0;
cs.gridwidth = 1;
panel.add(lbUsername, cs);
tfUsername = new JTextField(20);
cs.gridx = 1;
cs.gridy = 0;
cs.gridwidth = 2;
panel.add(tfUsername, cs);
lbPassword = new JLabel("Password: ");
cs.gridx = 0;
cs.gridy = 1;
cs.gridwidth = 1;
panel.add(lbPassword, cs);
tfPassword = new JPasswordField(20);
cs.gridx = 1;
cs.gridy = 1;
cs.gridwidth = 2;
panel.add(tfPassword, cs);
panel.setBorder(new LineBorder(Color.GRAY));
btnLogin = new JButton("Login");
btnLogin.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(Login.this,
"Hi ! You have successfully logged in.",
"Login", JOptionPane.INFORMATION_MESSAGE);
dispose();
//Here i need to open my new frame
new Steganography_Controller(new
Steganography_View("Steganography")
);
}
});
JPanel bp = new JPanel();
bp.add(btnLogin);
getContentPane().add(panel, BorderLayout.CENTER);
getContentPane().add(bp, BorderLayout.PAGE_END);
pack();
setResizable(false);
setLocationRelativeTo(parent);
dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
// setDefaultCloseOperation(JDialog.EXIT_ON_CLOSE);
}
public String getUsername() {
return tfUsername.getText().trim();
}
public String getPassword() {
return new String(tfPassword.getPassword());
}
public boolean isSucceeded() {
return succeeded;
}
public static void main(String args[]) {
Login l = new Login(frame);
l.setVisible(true);
}
}
这是Steganography_View
public class Steganography_View extends JFrame
{
//size variables for window
private static int WIDTH = 500;
private static int HEIGHT = 400;
//elements for JPanel
private JTextArea input;
//private JScrollBar scroll,scroll2;
private JButton encodeButton,decodeButton;
private JLabel image_input;
//elements for Menu
private JMenu file;
private JMenuItem encode;
private JMenuItem decode;
private JMenuItem sendfile;
private JMenuItem calculatepsnr;
private JMenuItem exit;
/*
*Constructor for Steganography_View class
*@param name Used to set the title on the JFrame
*/
public Steganography_View(String name)
{
//set the title of the JFrame
super(name);
//Menubar
JMenuBar menu = new JMenuBar();
file = new JMenu("File"); file.setMnemonic('F');
encode = new JMenuItem("Encode"); encode.setMnemonic('E'); file.add(encode);
decode = new JMenuItem("Decode"); decode.setMnemonic('D'); file.add(decode);
sendfile = new JMenuItem("Send File"); sendfile.setMnemonic('S'); file.add(sendfile);
calculatepsnr = new JMenuItem("Calculate PSNR"); calculatepsnr.setMnemonic('P'); file.add(calculatepsnr);
file.addSeparator();
exit = new JMenuItem("Exit"); exit.setMnemonic('x'); file.add(exit);
menu.add(file);
setJMenuBar(menu);
// display rules
setResizable(true); //allow window to be resized: true?false
setBackground(Color.lightGray); //background color of window: Color(int,int,int) or Color.name
setLocation(100,100); //location on the screen to display window
setDefaultCloseOperation(EXIT_ON_CLOSE);//what to do on close operation: exit, do_nothing, etc
setSize(WIDTH,HEIGHT); //set the size of the window
setVisible(true); //show the window: true?false
System.out.println("inside steganography_view");
}
/*
*@return The menu item 'Encode'
*/
public JMenuItem getEncode() { return encode; }
/*
*@return The menu item 'Send File'
*/
public JMenuItem getSendFile() { return sendfile; }
/*
*@return The menu item 'Decode'
*/
public JMenuItem getDecode() { return decode; }
/*
*@return The menu item 'Calculate PSNR'
*/
public JMenuItem getPSNR() { return calculatepsnr; }
/*
*@return The menu item 'Exit'
*/
public JMenuItem getExit() { return exit; }
/*
*@return The TextArea containing the text to encode
*/
public JTextArea getText() { return input; }
/*
*@return The JLabel containing the image to decode text from
*/
public JLabel getImageInput() { return image_input; }
/*
*@return The JPanel displaying the Encode View
*/
public JPanel getTextPanel() { return new Text_Panel(); }
/*
*@return The JPanel displaying the Decode View
*/
public JPanel getImagePanel() { return new Image_Panel(); }
/*
*@return The Encode button
*/
public JButton getEButton() { return encodeButton; }
/*
*@return The Decode button
*/
public JButton getDButton() { return decodeButton; }
private class Text_Panel extends JPanel
{
/*
*Constructor to enter text to be encoded
*/
public Text_Panel()
{
//setup GridBagLayout
GridBagLayout layout = new GridBagLayout();
GridBagConstraints layoutConstraints = new GridBagConstraints();
setLayout(layout);
input = new JTextArea();
layoutConstraints.gridx = 0; layoutConstraints.gridy = 0;
layoutConstraints.gridwidth = 1; layoutConstraints.gridheight = 1;
layoutConstraints.fill = GridBagConstraints.BOTH;
layoutConstraints.insets = new Insets(0,0,0,0);
layoutConstraints.anchor = GridBagConstraints.CENTER;
layoutConstraints.weightx = 1.0; layoutConstraints.weighty = 50.0;
JScrollPane scroll = new JScrollPane(input,JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
layout.setConstraints(scroll,layoutConstraints);
scroll.setBorder(BorderFactory.createLineBorder(Color.BLACK,1));
add(scroll);
encodeButton = new JButton("Encode Now");
layoutConstraints.gridx = 0; layoutConstraints.gridy = 1;
layoutConstraints.gridwidth = 1; layoutConstraints.gridheight = 1;
layoutConstraints.fill = GridBagConstraints.BOTH;
layoutConstraints.insets = new Insets(0,-5,-5,-5);
layoutConstraints.anchor = GridBagConstraints.CENTER;
layoutConstraints.weightx = 1.0; layoutConstraints.weighty = 1.0;
layout.setConstraints(encodeButton,layoutConstraints);
add(encodeButton);
//set basic display
setBackground(Color.lightGray);
setBorder(BorderFactory.createLineBorder(Color.BLACK,1));
}
}
/*
*Class Image_Panel
*/
private class Image_Panel extends JPanel
{
/*
*Constructor for displaying an image to be decoded
*/
public Image_Panel()
{
//setup GridBagLayout
GridBagLayout layout = new GridBagLayout();
GridBagConstraints layoutConstraints = new GridBagConstraints();
setLayout(layout);
image_input = new JLabel();
layoutConstraints.gridx = 0; layoutConstraints.gridy = 0;
layoutConstraints.gridwidth = 1; layoutConstraints.gridheight = 1;
layoutConstraints.fill = GridBagConstraints.BOTH;
layoutConstraints.insets = new Insets(0,0,0,0);
layoutConstraints.anchor = GridBagConstraints.CENTER;
layoutConstraints.weightx = 1.0; layoutConstraints.weighty = 50.0;
JScrollPane scroll2 = new JScrollPane(image_input,JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
layout.setConstraints(scroll2,layoutConstraints);
scroll2.setBorder(BorderFactory.createLineBorder(Color.BLACK,1));
image_input.setHorizontalAlignment(JLabel.CENTER);
add(scroll2);
decodeButton = new JButton("Decode Now");
layoutConstraints.gridx = 0; layoutConstraints.gridy = 1;
layoutConstraints.gridwidth = 1; layoutConstraints.gridheight = 1;
layoutConstraints.fill = GridBagConstraints.BOTH;
layoutConstraints.insets = new Insets(0,-5,-5,-5);
layoutConstraints.anchor = GridBagConstraints.CENTER;
layoutConstraints.weightx = 1.0; layoutConstraints.weighty = 1.0;
layout.setConstraints(decodeButton,layoutConstraints);
add(decodeButton);
//set basic display
setBackground(Color.lightGray);
setBorder(BorderFactory.createLineBorder(Color.BLACK,1));
}
}
最佳答案
它挂起的原因是因为您当前的线程正在侦听传入的连接（在事件调度线程中完成），从而被阻塞。它不会立即返回，而是等待连接。因此，用于监听连接的代码应在其自己的线程中：
代替FileTransfer(); /* <----- Here's....*/
在自己的线程中运行它：
Thread fileTransferThread = new Thread(new Runnable(){
public void run(){
FileTransfer();
}
});
fileTransferThread.start();