Question

被修改

我的问题是我制作了一个简单的客户端服务器程序，它启动一个简单的JFrame，但每次运行它时，套接字都会关闭，服务器终止，尽管我把它放在while循环中

我的服务器代码：

public class Server extends Thread{

Socket socket;
public Server(Socket socket)
{
    this.socket = socket;
}

public synchronized void run()
{
    try {  
        String connect = "Connecting Successfully :)";
        ObjectOutputStream out = new ObjectOutputStream(socket.getOutputStream());
        out.writeUTF(connect);
        Login l = new Login();
        l.setLocation(350, 250);
        l.setSize(400, 350);
        l.setTitle("Inventory Management System");
        l.setResizable(false);
        l.setVisible(true);
        out.writeObject(l);
        out.close();

    } catch (IOException ex) {
        JOptionPane.showMessageDialog(null, "IOException2: " + ex.getMessage() ,"Fatal Error", JOptionPane.ERROR_MESSAGE);
    }
}

public static void main(String argv[]) throws IOException{

    int i = 0;
    ServerSocket s1 = new ServerSocket(5000);
    while(i == 0)
    {
        Socket ss = s1.accept(); 
        new Server(ss).start();
    }
}
}

我的客户代码：

    public class Client{

    public static void main(String argv[])
    {

    try{
    Socket s = new Socket("localhost",5000);
    ObjectInputStream in = new ObjectInputStream(s.getInputStream());
    String connect = in.readUTF();
    JOptionPane.showMessageDialog(null, connect, "Server Success", JOptionPane.INFORMATION_MESSAGE);

    Login l = (Login)in.readObject();

    //in.close();

    } catch(ConnectException e){
        JOptionPane.showMessageDialog(null, "Failed to connect to the server.", "Connection Failed", JOptionPane.ERROR_MESSAGE);
    } catch(IOException e){
        JOptionPane.showMessageDialog(null, "IOException: " + e.getMessage(), "Fatal Error", JOptionPane.ERROR_MESSAGE);
    } catch (ClassNotFoundException ex) {
        JOptionPane.showMessageDialog(null, "ClassNotFoundException: " + ex.getMessage(), "Fatal Error", JOptionPane.ERROR_MESSAGE);
    }
    finally{
        JOptionPane.showMessageDialog(null, this , "Warining", JOptionPane.WARNING_MESSAGE);
    }
}
}

如何解决这个问题？

Answer 1

套接字不会自发关闭。你正在关闭套接字。这里：

out.close();

关闭套接字的输入或输出流会关闭套接字。

Answer 2

当我点击它时我有按钮它应该传递给另一个gui页面。

您的客户代码：

// connect socket
Socket ss = new Socket("localhost", 4000);

// create PrintStream from socket's output stream
// for **one way communication** from client to server only
PrintStream pr = new PrintStream(ss.getOutputStream(), true);

// push two Strings through socket
pr.println("Supplier Orders");
pr.println(Supplier.username);

// close GUI and possibly close program.
this.dispose();

因此，此代码似乎将2个字符串发送到服务器，然后尝试退出。

此外：
在您的服务器中，您使用while true循环完全绑定当前线程，如果这是在GUI事件线程上，GUI将“冻结”。您应该在后台线程中运行所有长时间运行的代码或线程暂停代码，这样它就不会妨碍GUI的事件线程。

如果仍然卡住，请再次创建并发布mcve。

修改
我尝试用你的代码制作一个mcve，这就是我得到的：

import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.net.ConnectException; import java.net.ServerSocket; import java.net.Socket; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.SwingConstants; public class HisSocket { public static void main(final String[] args) { new Thread(new Runnable() { @Override public void run() { try { Server.main(args); } catch (IOException e) { e.printStackTrace(); } } }).start(); new Thread(new Runnable() { @Override public void run() { Client.main(args); } }).start(); } } class Server extends Thread { Socket socket; public Server(Socket socket) { this.socket = socket; } public synchronized void run() { try { String connect = "Connecting Successfully :)"; ObjectOutputStream out = new ObjectOutputStream(socket.getOutputStream()); out.writeUTF(connect); Login l = new Login(); l.setLocation(350, 250); l.setSize(400, 350); l.setTitle("Inventory Management System"); l.setResizable(false); l.setVisible(true); out.writeObject(l); out.close(); } catch (IOException ex) { JOptionPane.showMessageDialog(null, "IOException2: " + ex.getMessage(), "Fatal Error", JOptionPane.ERROR_MESSAGE); } } public static void main(String argv[]) throws IOException { int i = 0; ServerSocket s1 = new ServerSocket(5000); while (i == 0) { Socket ss = s1.accept(); new Server(ss).start(); } } } class Login extends JFrame { public Login() { super("Login"); // setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); add(new JLabel("Login JFrame", SwingConstants.CENTER)); } } class Client { public static void main(String argv[]) { try { Socket s = new Socket("localhost", 5000); ObjectInputStream in = new ObjectInputStream(s.getInputStream()); String connect = in.readUTF(); JOptionPane.showMessageDialog(null, connect, "Server Success", JOptionPane.INFORMATION_MESSAGE); Login l = (Login) in.readObject(); // in.close(); } catch (ConnectException e) { JOptionPane.showMessageDialog(null, "Failed to connect to the server.", "Connection Failed", JOptionPane.ERROR_MESSAGE); } catch (IOException e) { JOptionPane.showMessageDialog(null, "IOException: " + e.getMessage(), "Fatal Error", JOptionPane.ERROR_MESSAGE); } catch (ClassNotFoundException ex) { JOptionPane.showMessageDialog(null, "ClassNotFoundException: " + ex.getMessage(), "Fatal Error", JOptionPane.ERROR_MESSAGE); } finally { // !! I couldn't use this because this doesn't exist in a static context // and so your code wouldn't compile. // JOptionPane.showMessageDialog(null, this, "Warining", // JOptionPane.WARNING_MESSAGE); JOptionPane.showMessageDialog(null, "client this", "Warining", JOptionPane.WARNING_MESSAGE); } } }

告诉我我应该体验的是什么。

打开JFrame时如何防止socket关闭？

2 个答案: