Springboot整合Mybatis-plus实现增删改查以及分页功能

最新推荐文章于 2025-06-01 15:14:22 发布

原创最新推荐文章于 2025-06-01 15:14:22 发布 · 247 阅读

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CC 4.0 BY-SA版权

文章标签：

#spring boot #mybatis #java

1.利用spring脚手架创建项目，引入基本依赖

大体项目结构

2.具体所需依赖

<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>3.0.4</version>
</dependency>

<dependency>
<groupId>com.mysql</groupId>
<artifactId>mysql-connector-j</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter-test</artifactId>
<version>3.0.4</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>1.4.6</version> <!-- 请使用最新版本 -->
<exclusions>
<exclusion>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
</exclusion>
</exclusions>
</dependency>

<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>5.3.0</version>
</dependency>

<!-- hutool 插件包 -->
<dependency>
<groupId>cn.hutool</groupId>
<artifactId>hutool-all</artifactId>
<version>5.8.25</version>
</dependency>
</dependencies>

3.在resources目录下创建yml文件连接数据库（application.yml）

server:
  port: 8080

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/你的数据库名
    username: 你的数据库用户名
    password: 你的数据库密码
    driver-class-name: com.mysql.cj.jdbc.Driver
mybatis:
  mapper-locations: classpath:mapper/*.xml
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
    map-underscore-to-camel-case: true

4.在springboot启动器添加扫描注解

@MapperScan("com.example.springboot.Mapper")

5.编写controller，service，mapper层

5.1 注意这儿还需要编写User实体类

package com.example.springboot.Entity;

public class User {
    private Integer id;
    private String name;
    private Integer age;
    private String sex;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }
}

5.2.注意引入Result类

package com.example.springboot.Common;

public class Result {
    private String code;
    private String msg;
    private Object data;


    public static Result success(){
        Result result=new Result();
        result.setCode("200");
        result.setMsg("请求成功");
        return result;
    }

    public static Result success(Object data){
        Result result = success();
        result.setData(data);
        return result;
    }

    public static Result error(){
        Result result=new Result();
        result.setCode("500");
        result.setMsg("系统错误");
        return result;
    }
    public static Result error(String code,String msg){
        Result result=new Result();
        result.setCode(code);
        result.setMsg(msg                        );
        return result;
    }
    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    public Object getData() {
        return data;
    }

    public void setData(Object data) {
        this.data = data;
    }
}

5.3 controller层

package com.example.springboot.Controller;


import com.example.springboot.Common.Result;
import com.example.springboot.Entity.User;
import com.example.springboot.Service.UserService;
import com.github.pagehelper.Page;
import com.github.pagehelper.PageInfo;
import jakarta.annotation.Resource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@RestController
@RequestMapping("/user")
public class UserController {
        @Resource
        @Autowired
    private UserService userService;
        @GetMapping("/selectAll")
    public Result selectAll(User user){
               List<User> list = userService.selectAll(user);
               return Result.success(list);
        }
        @GetMapping("/selectById/{id}")
    public Result selectById(@PathVariable Integer id){
           User user = userService.selectById(id);
            return Result.success(user);
    }
        @PostMapping("/add")
    public Result add(@RequestBody User user ){
            userService.add(user);
            return Result.success();
    }
        @PutMapping("/update")
    public Result updateById(@RequestBody User user){
            userService.updateById(user);
            return Result.success();
    }
        @DeleteMapping("/delete/{id}")
     public Result deleteById(@PathVariable Integer id){
            userService.deleteById(id);
            return Result.success();
     }
      @DeleteMapping("/deleteBatch")
     public Result deleteBatch(@RequestBody List<Integer> ids){
            userService.deleteBatch(ids);
            return Result.success();
     }
      @GetMapping("/selectPage")
     public Result selectPage(User user,
                              @RequestParam(defaultValue = "1") Integer pageNum,
                              @RequestParam(defaultValue = "10") Integer pageSize){
         PageInfo<User> pageInfo = userService.selectPage(user,pageNum,pageSize);
        return Result.success(pageInfo);
     }
}

5.4 Service层

package com.example.springboot.Service;

import com.example.springboot.Entity.User;
import com.example.springboot.Mapper.UserMapper;
import com.github.pagehelper.PageInfo;
import jakarta.annotation.Resource;
import org.springframework.stereotype.Service;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import java.util.List;
@Service
public class UserService {
    @Resource
    private UserMapper userMapper;
    public List<User> selectAll(User user) {
          return userMapper.selectAll(user);
    }

    public void deleteById(Integer id) {
        userMapper.deleteById(id);
    }

    public void add(User user) {
        userMapper.add(user);
    }

    public User selectById(Integer id) {
       return userMapper.selectById(id);
    }

    public void updateById(User user) {
        userMapper.updateById(user);
    }

    public void deleteBatch(List<Integer> ids) {
          for (Integer id : ids){
              this.deleteById(id);
          }
    }

    public PageInfo<User> selectPage(User user, Integer pageNum, Integer pageSize) {
        PageHelper.startPage(pageNum,pageSize);
        List<User> list = userMapper.selectAll(user);
        return PageInfo.of(list);
    }
}

5.5 Mapper层

package com.example.springboot.Mapper;

import com.example.springboot.Entity.User;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Select;

import java.util.List;

public interface UserMapper {
    public abstract List<User> selectAll(User user);

    @Delete("delete from `user` where id=#{id}")
    void deleteById(Integer id);

    void add(User user);
    @Select("select * from `user` where id=#{id}")
    User selectById(Integer id);

    void updateById(User user);
}

6.编写mybatis的sql映射xml文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.springboot.Mapper.UserMapper">
    <select id="selectAll" resultType="com.example.springboot.Entity.User">
        select * from user
        <where>
            <if test="name !=null">name like concat('%',#{name},'%')</if>
        </where>
        order by id desc
    </select>
</mapper>

前面忘了，数据库如下

CREATE TABLE `user` (
  `id` int NOT NULL AUTO_INCREMENT,
  `name` varchar(255) COLLATE utf8mb4_general_ci DEFAULT NULL,
  `age` int DEFAULT NULL,
  `sex` varchar(255) COLLATE utf8mb4_general_ci DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=13 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;

最后，启动项目即可实现所有功能！