The background system can manage classification information, classify dish classifications and set meal classifications. When we add dishes in the backend system, we need to select a dish category.
When we add a set meal in the backend system, we need to select a set meal category. The corresponding dishes and set meals will also be displayed on the mobile terminal according to the dish classification and set meal category.
At the same time, add the dish category and package category on the category management page of the backend system:
Add dish category
Add package category
##Data model: Involves one table Category table: The data JavaBean corresponding to the table is Category.javaCategory.javapackage com.itheima.reggie.entity; import com.baomidou.mybatisplus.annotation.FieldFill; import com.baomidou.mybatisplus.annotation.IdType; import com.baomidou.mybatisplus.annotation.TableField; import com.baomidou.mybatisplus.annotation.TableId; import lombok.Data; import lombok.Getter; import lombok.Setter; import java.io.Serializable; import java.time.LocalDateTime; /** * 分类 */ @Data public class Category implements Serializable { private static final long serialVersionUID = 1L; private Long id; //类型 1 菜品分类 2 套餐分类 private Integer type; //分类名称 private String name; //顺序 private Integer sort; //创建时间 @TableField(fill = FieldFill.INSERT) private LocalDateTime createTime; //更新时间 @TableField(fill = FieldFill.INSERT_UPDATE) private LocalDateTime updateTime; //创建人 @TableField(fill = FieldFill.INSERT) private Long createUser; //修改人 @TableField(fill = FieldFill.INSERT_UPDATE) private Long updateUser; //是否删除 private Integer isDeleted; }For the specific frame, please refer to the previous Employee entity construction. 1.2 Code DevelopmentThe service address requested for adding new dish categories and set meal categories is the same as the submitted JSON data structure. The server only needs to provide one method: API
Value | |
/category | |
{ | "name": "Sichuan cuisine", "type": "1", "sort": "1" } |
package com.itheima.reggie.controller; import com.itheima.reggie.common.R; import com.itheima.reggie.entity.Category; import com.itheima.reggie.service.CategoryService; import lombok.extern.slf4j.Slf4j; import org.springframework.web.bind.annotation.PostMapping; import org.springframework.web.bind.annotation.RequestBody; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import javax.annotation.Resource; /** * @author jektong * @date 2022年05月06日 21:47 */ @RestController @Slf4j @RequestMapping("/category") public class CategoryController { @Resource private CategoryService categoryService; /** * 新增分类 * @param category * @return */ @PostMapping public R<String> save(@RequestBody Category category){ log.info("category:{}",category); categoryService.save(category); return R.success("新增分类成功"); } }2. Category information paging queryPaging query is the same as the previous employee information query. Go directly to the code:
@GetMapping("/page") public R<Page> page(int page, int pageSize){ // 分页构造 Page<Category> pageInfo = new Page<Category>(page,pageSize); // 查询并排序 LambdaQueryWrapper<Category> queryWrapper = new LambdaQueryWrapper(); queryWrapper.orderByAsc(Category::getSort); // 分页查询 categoryService.page(pageInfo,queryWrapper); return R.success(pageInfo); }3. Delete category3.1 Requirements analysisIn the category management list Page, you can delete a category. It should be noted that when a category is associated with a dish or set meal, this category cannot be deleted. API
Value | |
/category?id= |
package com.itheima.reggie.entity; import com.baomidou.mybatisplus.annotation.FieldFill; import com.baomidou.mybatisplus.annotation.IdType; import com.baomidou.mybatisplus.annotation.TableField; import com.baomidou.mybatisplus.annotation.TableId; import lombok.Data; import java.io.Serializable; import java.math.BigDecimal; import java.time.LocalDateTime; /** 菜品 */ @Data public class Dish implements Serializable { private static final long serialVersionUID = 1L; private Long id; //菜品名称 private String name; //菜品分类id private Long categoryId; //菜品价格 private BigDecimal price; //商品码 private String code; //图片 private String image; //描述信息 private String description; //0 停售 1 起售 private Integer status; //顺序 private Integer sort; @TableField(fill = FieldFill.INSERT) private LocalDateTime createTime; @TableField(fill = FieldFill.INSERT_UPDATE) private LocalDateTime updateTime; @TableField(fill = FieldFill.INSERT) private Long createUser; @TableField(fill = FieldFill.INSERT_UPDATE) private Long updateUser; //是否删除 private Integer isDeleted; }Setmeal.java: Package entity
package com.itheima.reggie.entity; import com.baomidou.mybatisplus.annotation.FieldFill; import com.baomidou.mybatisplus.annotation.IdType; import com.baomidou.mybatisplus.annotation.TableField; import com.baomidou.mybatisplus.annotation.TableId; import lombok.Data; import java.io.Serializable; import java.math.BigDecimal; import java.time.LocalDateTime; /** * 套餐 */ @Data public class Setmeal implements Serializable { private static final long serialVersionUID = 1L; private Long id; //分类id private Long categoryId; //套餐名称 private String name; //套餐价格 private BigDecimal price; //状态 0:停用 1:启用 private Integer status; //编码 private String code; //描述信息 private String description; //图片 private String image; @TableField(fill = FieldFill.INSERT) private LocalDateTime createTime; @TableField(fill = FieldFill.INSERT_UPDATE) private LocalDateTime updateTime; @TableField(fill = FieldFill.INSERT) private Long createUser; @TableField(fill = FieldFill.INSERT_UPDATE) private Long updateUser; //是否删除 private Integer isDeleted; }3.2 Core codeCategoryServiceImpl.java
package com.itheima.reggie.service.impl; import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper; import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl; import com.itheima.reggie.common.CustomException; import com.itheima.reggie.entity.Category; import com.itheima.reggie.entity.Dish; import com.itheima.reggie.entity.Setmeal; import com.itheima.reggie.mapper.CategoryMapper; import com.itheima.reggie.service.CategoryService; import com.itheima.reggie.service.DishService; import com.itheima.reggie.service.SetmealService; import org.springframework.stereotype.Service; import javax.annotation.Resource; /** * @author jektong * @date 2022年05月06日 21:44 */ @Service public class CategoryServiceImpl extends ServiceImpl<CategoryMapper, Category> implements CategoryService { @Resource private DishService dishService; @Resource private SetmealService setmealService; /** * 根据ID删除分类,分类之前需要判断 * @param id */ @Override public void remove(Long id) { LambdaQueryWrapper<Dish> dishLambdaQueryWrapper = new LambdaQueryWrapper<>(); // 查询当前分类是否关联了菜品,若关联菜品,抛出异常 dishLambdaQueryWrapper.eq(Dish::getCategoryId,id); int count = dishService.count(dishLambdaQueryWrapper); if(count > 0){ // 已经关联菜品,抛出异常 throw new CustomException("当前分类已关联菜品,不可删除"); } // 查询当前分类是否关联了套餐,若关联菜品,抛出异常 LambdaQueryWrapper<Setmeal> setmealLambdaQueryWrapper = new LambdaQueryWrapper<>(); setmealLambdaQueryWrapper.eq(Setmeal::getCategoryId,id); int count1 = setmealService.count(setmealLambdaQueryWrapper); if(count>0){ // 已经关联套餐,抛出异常 throw new CustomException("当前分类已关联套餐,不可删除"); } // 正常删除分类 super.removeById(id); } }Add in the previous custom exception class:
/** * 异常处理方法 * @param customException * @return */ @ExceptionHandler(CustomException.class) public R<String> exceptionHandler(CustomException customException){ log.error(customException.getMessage()); return R.error(customException.getMessage()); }CustomException.java
package com.itheima.reggie.common; /** * @author jektong * @date 2022年05月10日 22:26 */ public class CustomException extends RuntimeException{ public CustomException(String msg){ super(msg); } }4. Modify the classification Modifying the classification is very simple. Just modify it according to the classification ID. The code is as follows:
@PutMapping public R<String> update(@RequestBody Category category){ log.info("修改分类信息{}" + category); categoryService.updateById(category); return R.success("分类修改成功"); }
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