public void update()
    {
        final double MS_TO_S = 0.001;

        long newMilliseconds = System.currentTimeMillis();
        double elapsedSeconds = (newMilliseconds - _lastMilliseconds) * MS_TO_S;

        // DEBUG
        // System.out.println(elapsedSeconds);

        _lastMilliseconds = newMilliseconds;

        for (Sprite sprite : _gumballs)
        {
            sprite.update(elapsedSeconds, _collisionSprites);
        }
    }