购物车模块实现代码块crud
需求：实现可选择对象，抽离并进行统一管理功能。
扩展：可以基于redis进行数据管理改造。
实例：
一、需求分析与设计
接口设计
-
请求方式：POST请求路径：/user/shoppingCart/add
-
请求参数：套餐id、菜品id、口味
-
返回结果：code、data、msg
（每一个接口都是类似的设计步骤。）
数据库设计
-
作用：暂时存放所选商品的地方
-
选的什么商品
-
每个商品都买了几个
-
不同用户的购物车需要区分开
（分表或添加冗余字段，可以提示查询速度。）
二、代码开发
1、接收对象设计
定义对象接收类
ShoppingCartDTO
import lombok.Data;
import java.io.Serializable;
@Data
public class ShoppingCartDTO implements Serializable {
private Long dishId;
private Long setmealId;
private String dishFlavor;
}定义数据库表对象类
ShoppingCart
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;
import java.math.BigDecimal;
import java.time.LocalDateTime;
/**
* 购物车
*/
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class ShoppingCart implements Serializable {
private static final long serialVersionUID = 1L;
private Long id;
//名称
private String name;
//用户id
private Long userId;
//菜品id
private Long dishId;
//套餐id
private Long setmealId;
//口味
private String dishFlavor;
//数量
private Integer number;
//金额
private BigDecimal amount;
//图片
private String image;
private LocalDateTime createTime;
}
2、业务层实现
1、Controller层
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;
@RestController
@RequestMapping("/user/shoppingCart")
@Slf4j
@Api(tags = "C端购物车相关接口")
public class ShoppingCartController {
@Autowired
private ShoppingCartService shoppingCartService;
/**
* 添加购物车
* @param shoppingCartDTO
* @return
*/
@PostMapping("/add")
@ApiOperation("添加购物车")
public Result add(@RequestBody ShoppingCartDTO shoppingCartDTO){
log.info("添加购物车，商品信息为：{}",shoppingCartDTO);
shoppingCartService.addShoppingCart(shoppingCartDTO);
return Result.success();
}
/**
* 查看购物车
* @return
*/
@GetMapping("/list")
@ApiOperation("查看购物车")
public Result> list(){
List list = shoppingCartService.showShoppingCart();
return Result.success(list);
}
/**
* 清空购物车
* @return
*/
@DeleteMapping("/clean")
@ApiOperation("清空购物车")
public Result clean(){
shoppingCartService.cleanShoppingCart();
return Result.success();
}
/**
* 删除购物车中一个商品
* @param shoppingCartDTO
* @return
*/
@PostMapping("/sub")
@ApiOperation("删除购物车中一个商品")
public Result sub(@RequestBody ShoppingCartDTO shoppingCartDTO){
log.info("删除购物车中一个商品，商品：{}", shoppingCartDTO);
shoppingCartService.subShoppingCart(shoppingCartDTO);
return Result.success();
}
} 2、Service
import java.util.List;
public interface ShoppingCartService {
/**
* 添加购物车
* @param shoppingCartDTO
*/
void addShoppingCart(ShoppingCartDTO shoppingCartDTO);
/**
* 查看购物车
* @return
*/
List showShoppingCart();
/**
* 清空购物车
*/
void cleanShoppingCart();
/**
* 删除购物车中一个商品
* @param shoppingCartDTO
*/
void subShoppingCart(ShoppingCartDTO shoppingCartDTO);
} impl
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.beans.beancontext.BeanContext;
import java.time.LocalDateTime;
import java.util.List;
@Service
@Slf4j
public class ShoppingCartServiceImpl implements ShoppingCartService {
@Autowired
private ShoppingCartMapper shoppingCartMapper;
@Autowired
private DishMapper dishMapper;
@Autowired
private SetmealMapper setmealMapper;
/**
* 添加购物车
* @param shoppingCartDTO
*/
public void addShoppingCart(ShoppingCartDTO shoppingCartDTO) {
//判断当前加入到购物车中的商品是否已经存在了
ShoppingCart shoppingCart = new ShoppingCart();
BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
Long userId = BaseContext.getCurrentId();
shoppingCart.setUserId(userId);
List list = shoppingCartMapper.list(shoppingCart);
//如果已经存在了，只需要将数量加一
if(list != null && list.size() > 0){
ShoppingCart cart = list.get(0);
cart.setNumber(cart.getNumber() + 1);//update shopping_cart set number = ? where id = ?
shoppingCartMapper.updateNumberById(cart);
}else {
//如果不存在，需要插入一条购物车数据
//判断本次添加到购物车的是菜品还是套餐
Long dishId = shoppingCartDTO.getDishId();
if(dishId != null){
//本次添加到购物车的是菜品
Dish dish = dishMapper.getById(dishId);
shoppingCart.setName(dish.getName());
shoppingCart.setImage(dish.getImage());
shoppingCart.setAmount(dish.getPrice());
}else{
//本次添加到购物车的是套餐
Long setmealId = shoppingCartDTO.getSetmealId();
Setmeal setmeal = setmealMapper.getById(setmealId);
shoppingCart.setName(setmeal.getName());
shoppingCart.setImage(setmeal.getImage());
shoppingCart.setAmount(setmeal.getPrice());
}
shoppingCart.setNumber(1);
shoppingCart.setCreateTime(LocalDateTime.now());
shoppingCartMapper.insert(shoppingCart);
}
}
/**
* 查看购物车
* @return
*/
public List showShoppingCart() {
//获取到当前微信用户的id
Long userId = BaseContext.getCurrentId();
ShoppingCart shoppingCart = ShoppingCart.builder()
.userId(userId)
.build();
List list = shoppingCartMapper.list(shoppingCart);
return list;
}
/**
* 清空购物车
*/
public void cleanShoppingCart() {
//获取到当前微信用户的id
Long userId = BaseContext.getCurrentId();
shoppingCartMapper.deleteByUserId(userId);
}
/**
* 删除购物车中一个商品
* @param shoppingCartDTO
*/
public void subShoppingCart(ShoppingCartDTO shoppingCartDTO) {
ShoppingCart shoppingCart = new ShoppingCart();
BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
//设置查询条件，查询当前登录用户的购物车数据
shoppingCart.setUserId(BaseContext.getCurrentId());
List list = shoppingCartMapper.list(shoppingCart);
if(list != null && list.size() > 0){
shoppingCart = list.get(0);
Integer number = shoppingCart.getNumber();
if(number == 1){
//当前商品在购物车中的份数为1，直接删除当前记录
shoppingCartMapper.deleteById(shoppingCart.getId());
}else {
//当前商品在购物车中的份数不为1，修改份数即可
shoppingCart.setNumber(shoppingCart.getNumber() - 1);
shoppingCartMapper.updateNumberById(shoppingCart);
}
}
}
} 3、mapper层
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Update;
import java.util.List;
@Mapper
public interface ShoppingCartMapper {
/**
* 动态条件查询
* @param shoppingCart
* @return
*/
List list(ShoppingCart shoppingCart);
/**
* 根据id修改商品数量
* @param shoppingCart
*/
@Update("update shopping_cart set number = #{number} where id = #{id}")
void updateNumberById(ShoppingCart shoppingCart);
/**
* 插入购物车数据
* @param shoppingCart
*/
@Insert("insert into shopping_cart (name, user_id, dish_id, setmeal_id, dish_flavor, number, amount, image, create_time) " +
" values (#{name},#{userId},#{dishId},#{setmealId},#{dishFlavor},#{number},#{amount},#{image},#{createTime})")
void insert(ShoppingCart shoppingCart);
/**
* 根据用户id删除购物车数据
* @param userId
*/
@Delete("delete from shopping_cart where user_id = #{userId}")
void deleteByUserId(Long userId);
/**
* 根据id删除购物车数据
* @param id
*/
@Delete("delete from shopping_cart where id = #{id}")
void deleteById(Long id);
/**
* 批量插入购物车数据
*
* @param shoppingCartList
*/
void insertBatch(List shoppingCartList);
}
ShoppingCartMapper.xml
insert into shopping_cart (name, image, user_id, dish_id, setmeal_id, dish_flavor, number, amount, create_time)
values
(#{sc.name},#{sc.image},#{sc.userId},#{sc.dishId},#{sc.setmealId},#{sc.dishFlavor},#{sc.number},#{sc.amount},#{sc.createTime})