mybatis-plus官网地址

https://www.baomidou.com/

maven依赖

 <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.3.0</version>
        <relativePath/> <!-- lookup parent from repository -->
</parent>
 <properties>
        <maven.compiler.source>17</maven.compiler.source>
        <maven.compiler.target>17</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- h2数据库依赖 -->
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <scope>test</scope>
        </dependency>
        <!--mybatis-plus配置-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.5.6</version>
        </dependency>
        <!--mybatis-spring的配置-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>3.0.3</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>    

数据库脚本

src/main/resources/db/schema-h2.sql

DROP TABLE IF EXISTS sys_user;

CREATE TABLE sys_user
(
    id BIGINT NOT NULL COMMENT '主键ID',
    name VARCHAR(30) NULL DEFAULT NULL COMMENT '姓名',
    age INT NULL DEFAULT NULL COMMENT '年龄',
    email VARCHAR(50) NULL DEFAULT NULL COMMENT '邮箱',
    PRIMARY KEY (id)
);

src/main/resources/db/data-h2.sql

DELETE FROM sys_user;

INSERT INTO sys_user (id, name, age, email) VALUES
(1, 'Jone', 18, 'test1@baomidou.com'),
(2, 'Jack', 20, 'test2@baomidou.com'),
(3, 'Tom', 28, 'test3@baomidou.com'),
(4, 'Sandy', 21, 'test4@baomidou.com'),
(5, 'Billie', 24, 'test5@baomidou.com');

配置文件

src/main/resources/application.yml

server:
  # 端口
  port: 9090
# 数据库配置
spring:
  datasource:
    # 驱动名称
    driver-class-name: org.h2.Driver
    # 自定义用户名
    username: root
    # 自定义密码
    password: test
    # 数据库地址:jdbc:h2:mem:数据库名称(随意填写，会自动创建
    url: jdbc:h2:mem:test
  h2:
    console:
      enabled: true
      path: /h2
      settings:
        web-allow-others: true
  sql:
    init:
      platform: h2
      # 数据库初始脚本
      schema-locations: classpath:db/schema-h2.sql
      # 数据库中表的初始脚本
      data-locations: classpath:db/data-h2.sql
# 日志输出级别
logging:
  level:
    com.example: debug

实体类

package org.example.entity;

import lombok.Data;

/**
 * @author 16837
 */
@Data
public class SysUser {
    private Long id;
    private String name;
    private Integer age;
    private String email;
}

Mapper

package org.example.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.example.entity.SysUser;

/**
 * @author 16837
 */
public interface SysUserMapper extends BaseMapper<SysUser> {
}

入门程序

package org.example;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * @author 16837
 */
@MapperScan("org.example.mapper")
@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

启动程序测试

访问路径: http://localhost:9090/h2

登录成功后的界面

单元测试

package org.example;

import jakarta.annotation.Resource;
import org.example.entity.SysUser;
import org.example.mapper.SysUserMapper;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import java.util.List;

@RunWith(SpringRunner.class)
@SpringBootTest(classes = Application.class, webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class ApplicationTest {

    @Resource
    private SysUserMapper userMapper;

    @Test
    public void testSelect() {
        System.out.println(("----- selectAll method test ------"));
        List<SysUser> userList = userMapper.selectList(null);
        userList.forEach(System.out::println);
    }

}

测试结果

Service层接口

package org.example.service;

import com.baomidou.mybatisplus.extension.service.IService;
import org.example.entity.SysUser;

public interface SysUserService extends IService<SysUser> {
}

package org.example.service.impl;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.example.entity.SysUser;
import org.example.mapper.SysUserMapper;
import org.example.service.SysUserService;
import org.springframework.stereotype.Service;

@Service
public class SysUserServiceImpl extends ServiceImpl<SysUserMapper, SysUser> implements SysUserService {
}

service层接口单元测试

package org.example;

import jakarta.annotation.Resource;
import org.example.entity.SysUser;
import org.example.mapper.SysUserMapper;
import org.example.service.SysUserService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import java.util.List;

@RunWith(SpringRunner.class)
@SpringBootTest(classes = Application.class, webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class ApplicationTest {

    @Resource
    private SysUserService userService;

    @Test
    public void testSelect() {
        System.out.println(("----- selectAll method test ------"));
        List<SysUser> userList = userService.list();
        userList.forEach(System.out::println);
    }

}

测试结果

项目结构