Come costruire una finestra

import javax.swing.*;public class Finestra1 { public void creaForm1(){ JFrame finestra1=new JFrame("finestra IVL"); finestra1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); finestra1.setSize(300,300); finestra1.setVisible(true); }
}

___________________________________________________________________________________

public class TestaFinestra1{ public static void main(String[] args){ Finestra1 f=new Finestra1(); f.creaForm1(); }
}