一个经典的多态Demo

class Car{static int num;int price;String name;Car(int price,String name){this.price = price;this.name = name;}public String getName() {return name;}public int getPrice() {return price;}public void sell(Car car){System.out.println("卖"+car.getName()+"车得到了"+car.getPrice());}}class BMW extends Car{public BMW(int a ,String name) {super(a, name);}public String getName() {return name;}public int getPrice() {return price;}}class bentian extends Car{bentian(int price, String name) {super(price, name);}public String getName() {return name;}public int getPrice() {return price;}}public class dtDemo {public static void main(String[] args) {Car car = new Car(100, "s");car.sell(new BMW(200, "BWM"));car.sell(new bentian(300, "Bentian"));}}