可變陰影

變數是 SHADOWED，方法是 OVERRIDDEN。將使用哪個變數取決於宣告變數的類。將使用哪種方法取決於變數引用的物件的實際類。

class Car {
    public int gearRatio = 8;

    public String accelerate() {
        return "Accelerate : Car";
    }
}

class SportsCar extends Car {
    public int gearRatio = 9;

    public String accelerate() {
        return "Accelerate : SportsCar";
    }

    public void test() {

    }

    public static void main(String[] args) {

        Car car = new SportsCar();
        System.out.println(car.gearRatio + "  " + car.accelerate());
        // will print out 8  Accelerate : SportsCar
    }
}