小码哥深入Node.js技术栈

class User {    private boolean vip;    public boolean isVip() {        return vip;    }}class PriceCalculator {    public int calculate(DiscountStrategy discountStrategy, int price, User user) throws IllegalAccessException {        // 每次新增一种策略就要多加一个类        return discountStrategy.discount(price, user);