springboot学习之四(整合mybatis)

springboot整合mybatis

 

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.29</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.3</version>
        </dependency>

 

 

 数据库及mybatis的配置

server.port=8080

#mysql配置
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=89757

#mybaits配置
#mybatis的为实体其别名
mybatis.type-aliases-package=com.cc8w.entity
#映射文件路径
mybatis.mapper-locations=classpath:mappers/*.xml
#日志控制台输出
mybatis.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl

数据库 （略）

实体类 （略）

 

1.mapper文件开发 （需配置mapper映射文件路径）

controller：

    @Autowired
    private TeacherService teacherService;
    @RequestMapping("/teacher")
    public String teacher(){
        List<TeacherEntity>  teachers =  teacherService.getTeacherAll();
        System.out.println(teachers);
        return teachers.toString();
    }

service：

@Service
public class TeacherService {

    @Autowired
    public TeacherMapper teacherMapper;
    public List<TeacherEntity> getTeacherAll(){
        List<TeacherEntity> teacherList = teacherMapper.queryOneTeacher(1);
        return teacherList;
    }
}

 

dao：

@Mapper
@Repository
public interface TeacherMapper {
    public List<TeacherEntity> queryOneTeacher(int id);
}

mapper文件(放在source下)：

<?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.cc8w.dao.TeacherMapper">
    <select id="queryOneTeacher" resultType="com.cc8w.entity.TeacherEntity">
    select * from teacher where id = #{id}
    </select>
</mapper>

 

 

2.纯注解开发 (不用再配置文件配置任何参数)

 

 纯注解开发，其实和注解的 controller,service ,都一致，不同的是 没有了接口和mapper.xml文件的对应（去掉了mapper.xml文件），直接在接口中写sql语句.

dao:

@Mapper
@Repository
public interface TeacherAnnoMapper {

    @Select("select * from teacher where 1")
    public List<TeacherEntity> queryTeachers();
}

 

 

 

 

https://www.cnblogs.com/fps2tao/p/13821490.html