🚀 go-pugleaf

I have read a article about making splash screen using java. The code like
this:
class SplashWindow1 extends JWindow
{
    public SplashWindow1(String filename, Frame f)
    {
        super(f);
        JLabel l = new JLabel(new ImageIcon(filename));
        getContentPane().add(l, BorderLayout.CENTER);
        pack();
        Dimension screenSize =
          Toolkit.getDefaultToolkit().getScreenSize();
        Dimension labelSize = l.getPreferredSize();
        setLocation(screenSize.width/2 - (labelSize.width/2),
                    screenSize.height/2 - (labelSize.height/2));
        setVisible(true);
        screenSize = null;
        labelSize = null;
    }
}

My question is how to make the instance of this class, if application is
starting without a frame how could we create this splash object.

Else what kind of paramater should we pass to the new instance of this class

Thanks
David