Overriding the paint method in JTextField to draw text

I am wishing to draw a number onto a JTextField by overwriting the paint method. So that when the user edits the text field the number doesn't disappear. However, at the moment, the number isn't appearing at all, I have tried:

public void paintComponent(Graphics g) {  
      super.paintComponent(g);
      if(number != 0){
             g.setColor(Color.RED);
             g.drawString(String.valueOf(number),0,0);
      }  
 }  
 

Any ideas, is this even possible?

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