public void moveCannonBalls(){
        // Move the cannonballs
        for(int i=0; i<cannons.size(); i++){
            CannonBall cannon = cannons.get(i);
            if(cannon.getDone()){
                try {
                    // Makes the "splashed" cannonball appear longer
                    Thread.sleep(10);
                } catch (InterruptedException ex) {
                    System.out.println(ex);
                    ex.printStackTrace();
                }
                cannons.remove(cannon);
            }
            else{
                cannon.move();
            }
        }// end for
    }