如何使顶部的摆动对话框窗口？

Question

After running the following example a dialog window appears under the active window, for example if a browser window active at the moment than dialog appears under it. How can I make dialog window appear on top of all windows in the system?

try {
    Thread.sleep(5000);
} catch (InterruptedException e) {
    e.printStackTrace();
}

JFrame frame = new JFrame("frame");
JOptionPane.showMessageDialog(
    frame,
    "test info",
    "test header",
    JOptionPane.INFORMATION_MESSAGE
);

Answer 1

Use

frame.setAlwaysOnTop(true);

before showing dialog..

       try {
            Thread.sleep(5000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        JFrame frame = new JFrame("frame");
        //it will keep this frame and its dialog always on top of the other frames/windows
        frame.setAlwaysOnTop(true);
        JOptionPane.showMessageDialog(
            frame,
            "test info",
            "test header",
            JOptionPane.INFORMATION_MESSAGE
        );

Answer 2

Add the following line under the frame declaration

JFrame frame = new JFrame("frame");
frame.setAlwaysOnTop(true);         

Thanks...