TestaFinestra java

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

finestra in java

import javax.swing.*;
public class Finestra1 {
public void creaForm1(){
JFrame finestra1=new JFrame("finestra IVL");
finestra1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
finestra1.setSize(500,300);
finestra1.setVisible(true);
}
}