解决问题:当有多种类型的会员时,订单计费的价格是有差异的,代码中太多的if和else必然导致代码的臃肿和难以维护,其实可以优雅的设计它。
1、定以订单类
@Service
@Slf4j
public class OrderServiceImpl implements OrderService {
//自动注入一个map(key是托管给Spring管理的引用名称,value为真实对象)
@Autowired
private Map<String, CalculateAmountService> calculateAmountServiceMap;
@Autowired
private ApplicationContext applicationContext;
@Override
public double getPaymentAmount(String userType, double amount) {
log.debug("所有的折扣对象:{}", calculateAmountServiceMap);
//根据用户的类型从map对象中找到对应的对象进行金额的计算
CalculateAmountService service = calculateAmountServiceMap.get(userType);
if (Objects.isNull(service)) {
return amount;
}
return service.getPaymentAmountByDisCount(amount);
}
}
2、定义不同用户类型计算的基类
package com.milla.navicat.spring.study.service;
/**
* @Package: com.milla.navicat.spring.study.service
* @Description: <根据不同的折扣计算不同的金额>
* @Author: MILLA
* @CreateDate: 2019/11/1 16:58
* @UpdateUser: MILLA
* @UpdateDate: 2019/11/1 16:58
* @UpdateRemark: <>
* @Version: 1.0
*/
public interface CalculateAmountService {
//根据用户的类型打折
double getPaymentAmountByDisCount(double fee);
}
3、具体实现类
3.1、普通会员实现类
package com.milla.navicat.spring.study.service.impl;
import com.milla.navicat.spring.study.service.CalculateAmountService;
import org.springframework.stereotype.Service;
/**
* @Package: com.milla.navicat.spring.study.service.impl
* @Description: <会员折扣>
* @Author: MILLA
* @CreateDate: 2019/11/1 16:59
* @UpdateUser: MILLA
* @UpdateDate: 2019/11/1 16:59
* @UpdateRemark: <>
* @Version: 1.0
*/
@Service(value = "normal")//托管处理时的引用名称
public class NormalCalculateAmountServiceImpl implements CalculateAmountService {
@Override
public double getPaymentAmountByDisCount(double fee) {
return fee * 0.9;
}
}
3.2、VIP会员实现类
package com.milla.navicat.spring.study.service.impl;
import com.milla.navicat.spring.study.service.CalculateAmountService;
import org.springframework.stereotype.Service;
/**
* @Package: com.milla.navicat.spring.study.service.impl
* @Description: <会员折扣>
* @Author: MILLA
* @CreateDate: 2019/11/1 16:59
* @UpdateUser: MILLA
* @UpdateDate: 2019/11/1 16:59
* @UpdateRemark: <>
* @Version: 1.0
*/
@Service(value = "vip")
public class VIPCalculateAmountServiceImpl implements CalculateAmountService {
@Override
public double getPaymentAmountByDisCount(double fee) {
return fee * 0.8;
}
}
3.3、金卡会员实现类
package com.milla.navicat.spring.study.service.impl;
import com.milla.navicat.spring.study.service.CalculateAmountService;
import org.springframework.stereotype.Service;
/**
* @Package: com.milla.navicat.spring.study.service.impl
* @Description: <至尊会员折扣>
* @Author: MILLA
* @CreateDate: 2019/11/1 16:59
* @UpdateUser: MILLA
* @UpdateDate: 2019/11/1 16:59
* @UpdateRemark: <>
* @Version: 1.0
*/
@Service(value = "gold")
public class GoldCalculateAmountServiceImpl implements CalculateAmountService {
@Override
public double getPaymentAmountByDisCount(double fee) {
return fee * 0.55;
}
}
3.4、超级会员实现类
package com.milla.navicat.spring.study.service.impl;
import com.milla.navicat.spring.study.service.CalculateAmountService;
import org.springframework.stereotype.Service;
/**
* @Package: com.milla.navicat.spring.study.service.impl
* @Description: <超级会员折扣>
* @Author: MILLA
* @CreateDate: 2019/11/1 16:59
* @UpdateUser: MILLA
* @UpdateDate: 2019/11/1 16:59
* @UpdateRemark: <>
* @Version: 1.0
*/
@Service(value = "svip")
public class SVIPCalculateAmountServiceImpl implements CalculateAmountService {
@Override
public double getPaymentAmountByDisCount(double fee) {
return fee * 0.5;
}
}
4、测试类
@RunWith(SpringRunner.class)
@SpringBootTest
@Slf4j
public class MyNavicatApplicationTests {
@Test
public void testDiscountByUserType() {
log.info("youke 类型的折扣:{}", saleService.getPaymentAmount("youke", 100));
log.info("normal 类型的折扣:{}", saleService.getPaymentAmount("normal", 100));
log.info("vip 类型的折扣:{}", saleService.getPaymentAmount("vip", 100));
log.info("svip 类型的折扣:{}", saleService.getPaymentAmount("svip", 100));
log.info("gold 类型的折扣:{}", saleService.getPaymentAmount("gold", 100));
}
}