接口与实现类的总结

Vehicle v2 = new Car();// v2 是 Car 类型

v2 是 Car 类型，而不是 Vehicle 类型。

class Vehicle {}public class Car extends Vehicle {    public static void main(String args[]){Car c1 = new Car();Vehicle v2 = new Car();// v2 是 Car 类型Vehicle v3 = new Vehicle();//Car 是 Vehicle类型, Vehicle 不是 Car 类型boolean result1 =  c1 instanceof Vehicle;// trueboolean result2 =  v2 instanceof Car;// trueboolean result3 =  v2 instanceof Vehicle;// trueboolean result4 =  v3 instanceof Car;  // falseSystem.out.println(result1);System.out.println(result2);System.out.println(result3);System.out.println(result4);   }}