Randomly Filling Tic Tac Toe Board

So I an assignment in Java to write a code which will randomly populate squares in a Tic Tac Toe Board. I pretty much have it I think, but I cannot get the 'O' to appear on the board, some squares will be blank. We were told to use the Random utility to generate the squares. I am attaching the .gif's which are used. Here is my code:

import javax.swing.*;
import java.awt.*;
import java.util.Random;
public class LandryTicTacToe extends JFrame
{
/**
*
*/
private static final long serialVersionUID = -8781512780135301721L;
private final int HEIGHT = 450;//Set value for Height
private final int WIDTH = 500;//Set value for Width
private static JButton [] button = new JButton[9];//Declare array of Buttons

[Code] .....

[attachment=37084:TicTac0.gif][attachment=37085:TicTacX.gif]

Instructions Given to me:

Display a frame that contains nine labels, arranged like a Tic Tac Toe board. A label may display an image icon for X, an image icon for O, or nothing. Display images randomly in each label. Use the Random class to generate 0, 1, or 2, which corresponds to displaying an X image, an O image, or nothing.

Attached image(s)