我正在创建一个客户端 - 服务器远程截图捕获应用程序。我可以成功地在服务器和客户端之间交换屏幕截图。但是一旦捕获并将屏幕截图发送到服务器，客户端就会从服务器断开连接。我希望客户端在捕获屏幕截图后保持连接。我是java输入/输出以及网络编程的新手。任何人都可以指出错误来帮助我吗？
以下是客户端的完整代码。如果还需要服务器代码来解决这个问题，我也会上传我的服务器代码。
客户端
public class ScreenClient {
public static void main(String[] args) throws Exception {
Robot robot = new Robot();
BufferedImage screen;
Socket server = new Socket("localhost", 5494);
BufferedReader bf = new BufferedReader(new InputStreamReader(server.getInputStream()));
String s;
s = bf.readLine();
System.out.println(s);
if (s.contains("execute")) {
Rectangle size = new Rectangle(Toolkit.getDefaultToolkit().getScreenSize());
screen = robot.createScreenCapture(size);
int[] rgbData = new int[(int) (size.getWidth() * size.getHeight())];
screen.getRGB(0, 0, (int) size.getWidth(), (int) size.getHeight(), rgbData, 0, (int) size.getWidth());
OutputStream baseOut = server.getOutputStream();
ObjectOutputStream out = new ObjectOutputStream(baseOut);
out.writeObject(size);
for (int x = 0; x < rgbData.length; x++) {
out.writeInt(rgbData[x]);
}
out.flush();
}
}
}
服务器
public class ScreenServer extends JFrame implements ActionListener {
String uname;
BufferedReader br;
static JTextArea taMessages, taUserList;
JTextField tfInput;
static Socket client;//
JButton btnCapture, btnExit, btnGetUsers;
static ArrayList<String> users = new ArrayList();
PrintWriter os;
public static void main(String[] args) throws Exception {
Robot robot = new Robot();
BufferedImage screen;
ScreenServer screenServer = new ScreenServer();
screenServer.buildInterface();
ServerSocket server = new ServerSocket(5494);
while (true) {
client = server.accept();
users.add(client.getInetAddress().getHostName());
InetAddress inet1 = client.getInetAddress();
broadcast(inet1.getHostName(), " Has connected!");
ObjectInputStream in = new ObjectInputStream(client.getInputStream());
Rectangle size = (Rectangle) in.readObject();
int[] rgbData = new int[(int) (size.getWidth() * size.getHeight())];
for (int x = 0; x < rgbData.length; x++) {
rgbData[x] = in.readInt();
}
screen = new BufferedImage((int) size.getWidth(), (int) size.getHeight(), BufferedImage.TYPE_INT_ARGB);
screen.setRGB(0, 0, (int) size.getWidth(), (int) size.getHeight(), rgbData, 0, (int) size.getWidth());
InetAddress clientAddress = client.getInetAddress();
String clientName = clientAddress.getHostName();
String t = (new Date()).toString();
ImageIO.write(screen, "png", new File(clientName + ".png"));
}
}
public void buildInterface() {
btnCapture = new JButton("Capture Screen");
btnExit = new JButton("Exit");
btnGetUsers = new JButton("Get Users");
//chat area
taMessages = new JTextArea();
taMessages.setRows(10);
taMessages.setColumns(50);
taMessages.setEditable(false);
//online users list
taUserList = new JTextArea();
taUserList.setRows(10);
taUserList.setColumns(10);
taUserList.setEditable(false);
//top panel (chat area and online users list
JScrollPane chatPanel = new JScrollPane(taMessages, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
JScrollPane onlineUsersPanel = new JScrollPane(taUserList, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
JPanel tp = new JPanel(new FlowLayout());
tp.add(chatPanel);
tp.add(onlineUsersPanel);
add(tp, "Center");
//user input field
tfInput = new JTextField(50);
//buttom panel (input field, send and exit)
JPanel bp = new JPanel(new FlowLayout());
bp.add(tfInput);
bp.add(btnCapture);
bp.add(btnExit);
bp.add(btnGetUsers);
add(bp, "South");
btnCapture.addActionListener(this);
tfInput.addActionListener(this);//allow user to press Enter key in order to send message
btnExit.addActionListener(this);
btnGetUsers.addActionListener(this);
setSize(500, 300);
setVisible(true);
pack();
}
@Override
public void actionPerformed(ActionEvent evt) {
if (evt.getSource() == btnExit) {
taMessages.setText(this.client + " has disconnected");
users.remove(this.client);
System.exit(0);
} else if (tfInput.getText().contains("!getusers")) {
taUserList.setText(" ");
this.getUsersOnline();
} else if (evt.getSource() == btnCapture) {
MessagesThread mt=new MessagesThread(client);
mt.start();
}
if (evt.getSource() == btnGetUsers) {
taUserList.setText("");
try {
// putUserOnline(this.client.getInetAddress().getHostName());
getUsersOnline();
} catch (NullPointerException nl) {
System.out.println("ERROR--> No Client Connection Found");
}
}
}
private void getUsersOnline() {
for (String s : users) {
putUserOnline(s);
}
}
public static void broadcast(String user, String message) {
// send message to all connected users
putMessage(user, message);
}
public static void putMessage(String uname, String msg) {
taMessages.append(uname + ": " + msg + "\n");
}
public static void putUserOnline(String name) {
taUserList.setText(name + ": " + "\n");
}
public class MessagesThread extends Thread {
Socket client;
public MessagesThread(Socket client) {
this.client = client;
}
@Override
public void run() {
String ClientName = tfInput.getText();
try {
String response = "execute";
if (users.contains(ClientName)) {
os = new PrintWriter(client.getOutputStream(), true);
os.println(response);
}
} catch (IOException ex) {
Logger.getLogger(ScreenServer.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
}