Why can't I draw my line without the use of an infinitely running while loop

I have to use a permanently running while loop to draw my line, otherwise the line renders for a millisecond and goes away. It may look fine but I may add hundreds upon hundreds of methods that would be running in one loop, that may cause some performance issues.

Debug (The main class)

public class Debug {
    public static void main(String[] args) {
        boolean running = true;
        Window test = new Window(800, 600, 100, 10, true, "This is the title");
        Renderer3D renderer = new Renderer3D();
        
        // my permanantly running while loop
        while (running) {
            renderer.draw();
        }

        test.addRenderer();
    }
}

Window (the class to create the window)

public class Window 
    static int width;
    static int height;
    static int x;
    static int y;
    static boolean v;
    static String title;
    
    public Window() {}
    
    public Window(int WIDTH, int HEIGHT, int X, int Y, boolean V, String TITLE) {
        // TODO Auto-generated constructor stub
        width = WIDTH;
        height = HEIGHT;
        x = X;
        y = Y;
        v = V;
        title = TITLE;
    }

    public static JFrame window = new JFrame();

    public void setWindowVisible(boolean v) {
        window.setVisible(v);
    }

    public void setWindowSize(int Width, int Height) {
        window.setSize(Width, Height);
    }

    public void setWindowLocation(int X, int Y) {
        window.setLocation(X, Y);
    }
    
    public void setWindowTitle(String TITLE) {
        window.setTitle(TITLE);
    }

    public static void displayProperties() {
        window.setSize(width, height);
        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.setLocation(x, y);
        window.setTitle(title);
        window.setVisible(v);
        window.setLocationRelativeTo(null);
    }
    
    public void addRenderer() {
        window.pack();
        displayProperties();
    }
    
    public JFrame returnWindow() {
        return window;
    }
}

Renderer (the class to draw things)

public class Renderer3D extends JFrame {
    public boolean executed;
    public boolean running = true;
    public Thread thread;

    public Canvas canvas = new Canvas() {
        public void paint(Graphics g) { 
        }
    };

    @SuppressWarnings("deprecation")
    public Renderer3D() {
        canvas.setBackground(Color.black);
        Window.window.add(canvas);
        Window.displayProperties();
        Window.window.show();
    }
    
    public void draw() {
        if (canvas == null) {
            canvas.createBufferStrategy(3);
        }
        
        Graphics g = canvas.getGraphics();
        g.setColor(Color.BLUE);
        g.drawLine(100, 100, 300, 300);
    }
}