JFrame 不会关闭

Question

I am working on a personal project to experiment with 2D physics. Right now, I am trying to set up the JFrame so that it updates 60 times per second. However, when I call the method to start updating the JFrame, I cannot close the JFrame. But if I leave out the part where I call the method, I can close the JFrame. This is the main code:

import javax.swing.JFrame;

import utils.Frame;

public class Engine {

    Frame w;
    
    boolean running = false;
    JFrame f;
    
    public void start() {
        init();
        updater();
    }
    
    public void init() {
        
        w = new Frame();
        
        running = true;
        f = w.create(500, 500, "Work please");
        
    }
    
    public void updater() {
        
        int fps = 60;
        double timePerTick = 1000000000 / fps;
        double delta = 0;
        long now;
        long lastTime = System.nanoTime();
        long timer = 0;

        while (running) {
            now = System.nanoTime();
            delta += now - lastTime;
            timer += now - lastTime;
            lastTime = now;

            if (delta >= timePerTick) {
                //render
                delta -= timePerTick;
            }

        }
    }
    
}

And this is the code for Frame:

import javax.swing.JFrame;

public class Frame {

    public JFrame create(int width, int height, String title) {

        JFrame f = new JFrame();
        f.setSize(width, height);
        f.setTitle(title);
        f.setLocationRelativeTo(null);
        f.setResizable(false);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setVisible(true);
        
        return f;
    }

}

If I don't call updater() in start(), I can close the JFrame. I know that I leave running = true, but it should still close because that would work on my old computer. And even if I need to make running = false, I already tried that by adding a WindowListener to f in Frame. It would call a method to make running = false, but for some reason the WindowListener wouldn't active when I hit the close button. Thank you for your help in advance. If this will help you in any way, I had to download a direct package of the Eclipse IDE from the website because every time I used the installer, every project would get the error "Failed to init ct.sym..." And for some reason, when I run a Java program with a JFrame in it, instead of the usual Jar logo, the Java mascot "Duke" shows up as the icon, which has been throwing me off.

Answer 1

Make sure you have two methods that control whether the program is running.

However make sure both methods are synchronized by using the-

synchronized

-keyword.

public synchronized void start() {
    if (running) return;
    running = true;
    thread = new Thread(this);
    thread.start();
}

public synchronized void stop() {
    if (!running) return;
    running = false;
    try {
        thread.join();
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
}