MybatisPlus—利用IService实现业务接口练习

练习：实现以下接口

代码目录

实体
        Po实体
        vo实体
        DTO实体

Controller层代码

Service接口

Service接口实现类

Mapper层

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实体

Po实体

package com.itheima.mp.domain.po;

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;

import java.time.LocalDateTime;

@Data
@TableName("tb_user")
public class User {

    @TableId(type= IdType.AUTO)
    private Long id;

    /**
     * 用户名
     */
    @TableField("`username`")
    private String username;

    /**
     * 密码
     */
    private String password;

    /**
     * 注册手机号
     */
    private String phone;

    /**
     * 详细信息
     */
    private String info;

    /**
     * 使用状态（1正常 2冻结）
     */
    private Integer status;

    /**
     * 账户余额
     */
    private Integer balance;

    /**
     * 创建时间
     */
    private LocalDateTime createTime;

    /**
     * 更新时间
     */
    private LocalDateTime updateTime;
}

vo实体

package com.itheima.mp.domain.vo;

import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;

@Data
@ApiModel(description = "用户VO实体")
public class UserVO {

    @ApiModelProperty("用户id")
    private Long id;

    @ApiModelProperty("用户名")
    private String username;

    @ApiModelProperty("详细信息")
    private String info;

    @ApiModelProperty("使用状态（1正常 2冻结）")
    private Integer status;

    @ApiModelProperty("账户余额")
    private Integer balance;
}

DTO实体

package com.itheima.mp.domain.dto;

import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.extension.handlers.JacksonTypeHandler;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;

@Data
@ApiModel(description = "用户表单实体")
public class UserFormDTO {

    @ApiModelProperty("id")
    private Long id;

    @ApiModelProperty("用户名")
    private String username;

    @ApiModelProperty("密码")
    private String password;

    @ApiModelProperty("注册手机号")
    private String phone;

    @ApiModelProperty("详细信息，JSON风格")
    private String info;

    @ApiModelProperty("账户余额")
    private Integer balance;
}

---

Controller层代码

package com.itheima.mp.controller;
import cn.hutool.core.bean.BeanUtil;
import com.itheima.mp.domain.dto.UserFormDTO;
import com.itheima.mp.domain.vo.UserVO;
import com.itheima.mp.domain.po.User;
import com.itheima.mp.service.UserService;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import io.swagger.annotations.ApiParam;
import lombok.RequiredArgsConstructor;
import org.springframework.web.bind.annotation.*;
import java.util.List;

@Api(tags = "用户管理接口")
@RequestMapping("/users")
@RestController
@RequiredArgsConstructor
public class UserController {

    private final UserService userService;

    @ApiOperation("新增用户接口")
    @PostMapping
    public void saveUser(@RequestBody UserFormDTO userDTO) {
        //1. save接收的是User对象，因此要把DTO拷贝到PO
        User user = BeanUtil.copyProperties(userDTO, User.class);
        //2. 新增
        userService.save(user);
    }

    @ApiOperation("删除用户接口")
    @DeleteMapping("{id}")
    public void deleteUser(@ApiParam("用户id") @PathVariable("id") Long id) {
        userService.removeById(id);
    }

    @ApiOperation("根据id查询用户接口")
    @GetMapping("{id}")
    public UserVO queryUserById(@ApiParam("用户id") @PathVariable("id") Long id) {
        //1. 查询用户PO
        User user = userService.getById(id);
        //2. 把PO拷贝到VO
        return BeanUtil.copyProperties(user, UserVO.class);
    }

    @ApiOperation("根据id批量查询")
    @GetMapping
    public List<UserVO> queryUserById(@ApiParam("用户id集合") @RequestParam("ids") List<Long> ids) {
        //1. 查询用户PO
        List<User> users = userService.listByIds(ids);
        //2. 把PO拷贝到VO
        return BeanUtil.copyToList(users, UserVO.class);
    }

    @ApiOperation("扣减用户余额接口")
    @PutMapping("/{id}/deduction/{money}")
    public void deductionMoneyById(
            @ApiParam("用户id") @PathVariable("id") Long id,
            @ApiParam("扣减的金额") @PathVariable("money") Integer money) {
        userService.deductBalance(id,money);
    }


}

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Service接口

package com.itheima.mp.service;

import com.baomidou.mybatisplus.extension.service.IService;
import com.itheima.mp.domain.po.User;
import org.springframework.stereotype.Service;

public interface UserService extends IService<User> {
    void deductBalance(Long id, Integer money);
}

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Service接口实现类

package com.itheima.mp.service.impl;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.itheima.mp.domain.po.User;
import com.itheima.mp.mapper.UserMapper;
import com.itheima.mp.service.UserService;
import org.springframework.stereotype.Service;

@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {

    @Override
    public void deductBalance(Long id, Integer money) {
        //1. 查询用户
        User user = getById(id);
        //2. 校验用户状态
        if (user == null || user.getStatus() == 2) {
            throw new RuntimeException("用户状态异常！");
        }
        //3. 校验余额是否充足
        if (user.getBalance() <= money) {
            throw new RuntimeException("用户余额不足！");
        }
        //4. 扣减余额
        baseMapper.deductBalance(id, money);
    }
}

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Mapper层

package com.itheima.mp.mapper;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.itheima.mp.domain.po.User;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Update;

@Mapper
//<>中放置你需要CRUD的实体类型
public interface UserMapper extends BaseMapper<User> {

    @Update("UPDATE tb_user SET balance = balance - #{money} WHERE id = #{id}")
    void deductBalance(@Param("id") Long id, @Param("money") Integer money);

}

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