[RESOLVED] Using layouts to place objects?

Could really use some help with a homework problem. I need to display a numeric keypad, above the keypad show a label that displays numbers picked, to the right of keypad is another button to clear display. It says to user a border layout to manage overall presentation and grid layout to manage keypad buttons. Put a border around keypad buttons and a border around the display.

I'm not asking anyone to do it because I do want to understand it but I can't get any further at this point, so I could use some help.

I had gotten the grid with the keypad but now I'm not sure how to nest it within a border?

The errors say I'm trying to add the container's parent to itself. I'm trying to put a border around it, I don't understand how this works?

Exception in thread "main" java.lang.IllegalArgumentException: adding container's parent to itself
at java.awt.Container.addImpl(Container.java:1017)
at java.awt.Container.add(Container.java:352)
at KeyPadPanel.<init>(KeyPadPanel.java:42)
at KeyPadDemo.main(KeyPadDemo.java:12)

Code:

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import java.awt.*;
import javax.swing.*;

public class KeyPadPanel extends JPanel
{


  public KeyPadPanel()
        {
          JPanel panel = new JPanel();
                setLayout (new GridLayout (4,3));
                panel.setBorder (BorderFactory.createLineBorder (Color.BLACK, 2));


               
                setBackground (Color.green);
               
                JButton b1 = new JButton ("1");
                JButton b2 = new JButton ("2");
                JButton b3 = new JButton ("3");
                JButton b4 = new JButton ("4");
                JButton b5 = new JButton ("5");
                JButton b6 = new JButton ("6");
                JButton b7 = new JButton ("7");
                JButton b8 = new JButton ("8");
                JButton b9 = new JButton ("9");
                JButton b10 = new JButton ("#");
                JButton b11 = new JButton ("0");
                JButton b12 = new JButton ("*");
               
                add (b1);
                add (b2);
                add (b3);
                add (b4);
                add (b5);
                add (b6);
                add (b7);
                add (b8);
                add (b9);
                add (b10);
                add (b11);
                add (b12);
                panel.add(panel);
        }       
}

---

the driver class

Code:

---

import javax.swing.*;


public class KeyPadDemo extends JPanel
{

  public static void main (String[] args)
        {
      JFrame frame = new JFrame ("KeyPad Demo");
                frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
               
                KeyPadPanel panel = new KeyPadPanel();
                frame.getContentPane().add (panel);
               
                frame.pack();
                frame.setVisible(true);       
        }
       
}

---