I have a class (let's call it Vehicle) and a subclass (Car). Instances of both are stored in one ArrayList. Car has a method that isn't inherited from vehicle, doStuff(). I want to doStuff() to every car in the ArrayList. This is the easiest solution I came up with:

```
vehicleList = new ArrayList<Vehicle>();
            roster.add(new Vehicle());
            roster.add(new Car());

            for (Vehicle v: vehicleList){
                    if (v instanceof Car){
                            ((Car) v).doStuff();
                    }
            }

```

But I feel like there's a much simpler way to do it. So thanks in advance if you can offer a simpler solution.