class Car
{
	class Wheel
	{
	}
}

class PlaneWheel extends Car.Wheel
{       
        //在派生類構造父類，
        PlaneWheel(Car car)
        {
                car.super();
        }
        
	public static void main(String[] args)
	{
	        Car car = new Car();
		PlaneWheel pw = new PlaneWheel(car);
	}
}