SpringBoot整合MyBatis-Plus完整详细版（提供Gitee源码）

前言：本篇文章完整详细介绍了SpringBoot整合MyBatis-Plus的完整过程，这边我的SpringBoot版本是2.4版本、JDK1.8和Maven3.8.1版本，跟着文章一步步走就可以了，MyBatis-Plus整合非常方便，也是现在企业开发中经常会用的一个持久层框架。

目录

一、导入依赖

二、yml配置文件

三、实现核心逻辑

3.1、新增实体类

3.2、新增持久层

3.3、实现服务层

四、实现增删查改 

4.1、新增数据

4.2、修改数据

4.3、删除数据

4.4、基础查询

4.5、自定义查询

五、Gitee源码 

---

一、导入依赖

在pom.xml文件中引入如下依赖：

        <!-- MyBatis-Plus -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.5.1</version>
        </dependency>
 
        <!-- 数据库驱动 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.28</version>
        </dependency>
 
        <!-- Lombok (可选) -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.24</version>
            <scope>provided</scope>
        </dependency>

二、yml配置文件

完整代码：

server:
  port: 9090
 
spring:
  datasource:
    username: 用户名
    password: 密码
    url: jdbc:mysql://ip地址:3306/数据库?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=UTC
    driver-class-name: com.mysql.cj.jdbc.Driver
 
mybatis-plus:
  # 搜索指定包别名（改成自己的）
  typeAliasesPackage: com.example.mybatisplus.domain
  # 配置mapper的扫描，找到所有的mapper.xml映射文件
  mapperLocations: classpath*:mapper/**/*Mapper.xml
  configuration:
    # 其他 MyBatis 配置
    map-underscore-to-camel-case: true  # 将数据库下划线转为驼峰命名
    cache-enabled: false  # 是否开启二级缓存
    lazy-loading-enabled: true  # 是否开启懒加载
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl  # 设置Mybatis的日志实现类为控制台输出

三、实现核心逻辑

实现Service、Mapper和Xml三个核心文件，先看一下项目整体结构：

3.1、新增实体类

package com.example.mybatisplus.domain;
 
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.util.Date;
import com.fasterxml.jackson.annotation.JsonFormat;
 
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Student {
 
    /**
     * 主键
     */
    @TableId(type = IdType.AUTO)
    private Integer id;
 
 
    /**
     * 姓名
     */
 
    private String name;
 
 
    /**
     * 性别
     */
 
    private String sex;
 
 
    /**
     * 电话
     */
 
    private String phone;
 
 
    /**
     * 地址
     */
 
    private String address;
 
 
    /**
     * 电子邮箱
     */
 
    private String email;
 
 
    /**
     * 入学时间
     */
    @JsonFormat(pattern = "yyyy-MM-dd")
    private Date registerTime;
 
 
    /**
     * 毕业时间
     */
    @JsonFormat(pattern = "yyyy-MM-dd")
    private Date graduateTime;
 
 
    /**
     * 学号
     */
 
    private String number;
 
 
    /**
     * 所属班级
     */
 
    private String className;
 
 
    /**
     * 用户ID
     */
 
    private Integer userId;
 
}
 
 
 

3.2、新增持久层

package com.example.mybatisplus.mapper;
 
import java.util.List;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.example.mybatisplus.domain.Student;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;
 
@Mapper
@Repository
public interface StudentMapper extends BaseMapper<Student>
{
 
    /**
     * 查询
     * @param student
     * @return
    */
    public List<Student> selectStudentList(Student student);
 
}

3.3、实现服务层

package com.example.mybatisplus.service;
 
import javax.annotation.Resource;
import java.util.List;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.example.mybatisplus.domain.Student;
import com.example.mybatisplus.mapper.StudentMapper;
import org.springframework.stereotype.Service;
 
@Service
public class StudentService extends ServiceImpl<StudentMapper, Student> {
 
    @Resource
    private StudentMapper studentMapper;
 
    public List<Student> selectStudentList(Student student) {
        return studentMapper.selectStudentList(student);
    }
 
 
}

 4.4、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.mybatisplus.mapper.StudentMapper">
 
    <select id="selectStudentList" resultType="Student">
        select * from student
        <where>
            <if test="id != null "> and id = #{id} </if>
            <if test="name != null and name != ''"> and name like concat('%', #{name}, '%') </if>
            <if test="sex != null and sex != ''"> and sex like concat('%', #{sex}, '%') </if>
            <if test="phone != null and phone != ''"> and phone like concat('%', #{phone}, '%') </if>
            <if test="address != null and address != ''"> and address like concat('%', #{address}, '%') </if>
            <if test="email != null and email != ''"> and email like concat('%', #{email}, '%') </if>
            <if test="registerTime != null "> and register_time = #{registerTime} </if>
            <if test="graduateTime != null "> and graduate_time = #{graduateTime} </if>
            <if test="number != null and number != ''"> and number like concat('%', #{number}, '%') </if>
            <if test="className != null and className != ''"> and class_name like concat('%', #{className}, '%') </if>
            <if test="userId != null "> and user_id = #{userId} </if>
        </where>
    </select>
 
</mapper>

四、实现增删查改 

以下是代码示例。

4.1、新增数据

    @Resource
    private StudentService studentService;
 
    public void insert(){
        Student student = new Student();
        student.setName("张三");
        student.setSex("1");
        student.setPhone("18888888");
        student.setEmail("199999@qq.com");
        student.setRegisterTime(new Date());
        student.setGraduateTime(new Date());
        student.setNumber("187891124");
        student.setClassName("高三1班");
        student.setUserId(109);
        studentService.save(student);
    }

4.2、修改数据

    @Resource
    private StudentService studentService;
 
    public void update(){
        //根据id获取
        Student student = studentService.getById(2);
        student.setName("李四");
        student.setSex("0");
        student.setPhone("15555555");
        student.setEmail("16556224@qq.com");
        studentService.updateById(student);
    }

4.3、删除数据

    @Resource
    private StudentService studentService;
    
    public void delete(){
        studentService.removeById(1);
    }

4.4、基础查询

    @Resource
    private StudentService studentService;
    
    public void select() {
        Student query = new Student();
        query.setName("张三");
        List<Student> studentList = studentService.selectStudentList(query);
        for(Student student : studentList){
            System.out.println(student);
        }
    }

4.5、自定义查询

    @Resource
    private StudentMapper studentMapper;
 
    public void query(){
        List<Integer> ids = new ArrayList<>();
        ids.add(9);
        ids.add(10);
        LambdaQueryWrapper<Student> lambdaQueryWrapper = new LambdaQueryWrapper<Student>();
        //小于当前时间
        lambdaQueryWrapper.lt(Student::getRegisterTime,new Date());
        //包含的id
        lambdaQueryWrapper.in(Student::getId,ids);
        List<Student> list = studentMapper.selectList(lambdaQueryWrapper);
        System.out.println(list);
    }

五、Gitee源码 

源码地址：SpringBoot整合MyBatis-Plus完整详细版