Swing JPanel with background image

This code add an image to Jpanel.

JPanel panel1 = new JPanel();
JFrame recursion_frame = new JFrame();

BackgroundPanel stack_image1 = new BackgroundPanel("Recursion.jpg");

panel1.setLayout(null);
panel1.setLayout(new BorderLayout());
panel1.setBackground(Color.lightGray);
panel1.setVisible(true);
recursion_frame.setContentPane(panel1);  ///adding to panel...
recursion_frame.getContentPane().add(stack_image1);  //adding image to panel...