读书笔记：开闭原则.zip

package com.example.principles; import org.springframework.lang.NonNull; import org.springframework.stereotype.Service; import java.util.HashMap; import java.util.List; import java.util.Map; @Service public class CouponServiceV2 { /** * 将折扣类型保存到这个Map中 */ Map<String, Discount> discountMap = new HashMap<>(16); public CouponServiceV2(List<Discount> discounts) { discounts.forEach(discount -> { this.discountMap.put(discount.getCouponType(), discount); }); } /** * 根据优惠券的类型进行金额计算 * * @param type * @param count * @return */ public double calculate(@NonNull CouponConstant type, @NonNull double count) { return discountMap.get(type.toString()).discount(count); } }