Changing Icon of a JLabel

Good day friends,

What I am trying to do is change the Icon of a label,depending on the value of a variable.

What I did is this :

 ImageIcon icon = new ImageIcon("C:\\Dice_2.jpg");
       if(roll==2) lbl_dice.setIcon(icon);

But it wont work.I also get no errors.
What happens is that when roll==2,the label just disappears...