// My first JDialog classimport javax.swing.*;import java.awt.*;import java.awt.event.*;public class myDialog1 extends JDialog{ public myDialog1 () { Container cont = getContentPane(); setTitle(" Hello "); setLayout(null); setSize(200,200); cont.setBackground(Color.BLACK); }}// My second JDialog classimport javax.swing.*;import java.awt.*;import java.awt.event.*;public class myDialog2 extends myDialog1{ public myDialog2 () { super(); getContentPane().setBackground(Color.WHITE); }}// How do I change the background color in myDialog2 ?