一篇超详细的Spring Boot整合Mybatis文章

配置文件形式

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-parent</artifactId>
       <version>2.4.4</version>
       <relativePath/> <!-- lookup parent from repository -->
   </parent>
   <groupId>com.keafmd</groupId>
   <artifactId>spring-boot-09-mybatis</artifactId>
   <version>0.0.1-SNAPSHOT</version>
   <name>spring-boot-09-mybatis</name>
   <description>Demo project for Spring Boot</description>
   <properties>
       <java.version>1.8</java.version>
   </properties>
   <dependencies>
       <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-jdbc</artifactId>
       </dependency>
       <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>1.3.2</version>
       </dependency>
       <dependency>
           <groupId>mysql</groupId>
           <artifactId>mysql-connector-java</artifactId>
           <scope>runtime</scope>
       </dependency>
       <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-test</artifactId>
           <scope>test</scope>
       </dependency>
   </dependencies>
   <build>
       <plugins>
           <plugin>
               <groupId>org.springframework.boot</groupId>
               <artifactId>spring-boot-maven-plugin</artifactId>
           </plugin>
       </plugins>
   </build>

</project>

配置数据源

在yml文件中配置数据源。

application.yml：

server:
 port: 80

# 配置数据源
spring:
 datasource:
   url: jdbc:mysql://127.0.0.1:3306/ssm-java1?useSSL=false
   driver-class-name: com.mysql.cj.jdbc.Driver
   username: root
   password: 18044229

# 整合mybatis
mybatis:
 #  typeAliasesPackage: com.neuedu.entity
 mapper-locations: classpath*:com/neuedu/boot/mapper/*.xml

UserMapper.xml

这里注意!!!:一定是和UserMapper相同的目录，是个 * 目录，创建时仿照这样创建com/keafm/mapper(正确的) 别这样com.keafam.mapper(错误的)，这样错误的创建的话，是个一级目录，不是 * 的，后面运行的时候可能会提示找不到Mapper。

<?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.keafmd.mapper.UserMapper">
   <select id="list" resultType="map">
       select * from user
   </select>
</mapper>

UserMapper

package com.keafmd.mapper;
import org.apache.ibatis.annotations.Mapper;
import java.util.List;
/**
* Keafmd
*
* @ClassName: UserMapper
* @Description:
* @author: 牛哄哄的柯南
* @Date: 2021-04-08 16:09
* @Blog: https://keafmd.blog.csdn.net/
*/
public interface UserMapper {
   List list();
}

配置springboot整合mybatis

在application.yml中配置：

# 整合mybatis
mybatis:
 #  typeAliasesPackage: com.neuedu.entity
 mapper-locations: classpath*:com/neuedu/boot/mapper/*.xml

在运行类上添加@MapperScan注解

SpringBoot09MybatisApplication：

package com.keafmd;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
@MapperScan("com.keafmd.mapper")
public class SpringBoot09MybatisApplication {
   public static void main(String[] args) {
       SpringApplication.run(SpringBoot09MybatisApplication.class, args);
   }
}

测试类

UserMapperTest ：

package com.keafmd.mapper;
import com.keafmd.SpringBoot09MybatisApplication;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import java.util.List;
import static org.junit.jupiter.api.Assertions.*;
@SpringBootTest(classes = SpringBoot09MybatisApplication.class)
class UserMapperTest {
   @Autowired
   UserMapper userMapper;
   @Test
   void list(){
       List list = userMapper.list();
       for (Object o : list) {
           System.out.println(o);
       }
   }
}

效果

来源：https://blog.csdn.net/weixin_43883917/article/details/115528174