Creación ventana de windows.

Codigo:

1. import javax.swing.*;
2. import java.awt.*;
3. public class Ventana extends JFrame {
4. ..public Ventana() {
5. ....Container c = getContentPane();
6. ....c.setLayout(new FlowLayout());
7. ....this.setSize(250,150);
8. ....this.setTitle("Titulo ventana");
9. ....this.setDefaultCloseOperation(EXIT_ON_CLOSE);
10. ....this.setVisible(true);
11. ..}
12. ..public static void main (String [] args) {
13. ....Ventana v = new Ventana();
14. ..}
15. }

Resultado: