Springboot整合Mybatis

1.创建springboot项目

File-->New->project->Spring Initializr->next->next->next->finish

注意选择包依赖关系

 

 

 完整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>2.4.3</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>demo1</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo1</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-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.4</version>
        </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>

2.在application.properties文件中加入

#数据路连接信息
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf8
spring.datasource.username=root
spring.datasource.password=root

#spring集成Mybatis环境
#pojo别名扫描包
mybatis.type-aliases-package=com.lamoun.pojo
#加载Mybatis映射文件
mybatis.mapper-locations=classpath:mapper/*Mapper.xml

3.实体类

@Data
public class User {
    private String username;
    private String password;
    private String id;
}

4.mapper层

@Mapper
public interface UserMapper {
    public List<User> queryUserList();
}

5.resources目录下的mapper目录

在resources目录下新建mapper目录，并在这个目录下新建UserMapper.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.lamoun.mapper.UserMapper">
    <select id="queryUserList" resultType="user">
         select * from user
    </select>
</mapper>

6.Controller层

@Controller
public class UserController {
    @Autowired
    private UserMapper mapper;

    @RequestMapping("/query")
    @ResponseBody
    public List<User> query(){
        List<User> users = mapper.queryUserList();
        return users;
    }
}

7.测试