grid and fractions

I have created a 3*3 grid using buttons but i want to hide the items that is stored in the buttons and have the user click on a button to reveal a fraction. If the user find two match then the program tally a score.

How do i implement this?

Code:

class RayFractions extends JFrame implements ActionListener, ItemListener {

   JButton one = new JButton.("1/2");
   JButton two = new JButton("2/4");
   JButton three = new JButton("3/9");
   JButton four = new JButton("4/8");
   JButton five = new JButton("5/6");
   JButton six = new JButton("6/9");
   JButton seven = new JButton("7/5");
   JButton eight = new JButton("8/8");
   JButton nine = new JButton("4/9");