SpringBoot入门二：与Mybatis整合

一、编程步骤

1、引入依赖

springboot相关依赖（略）、mybatis-spring-boot-starter、mysql、druid、lombook

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.1.4</version>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.2.5</version>
</dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
</dependency>

2、整合mybatis

1）建表

2）实体类：使用lombook

@Data
@Accessors(chain = true)
@NoArgsConstructor
@AllArgsConstructor
public class User {
    private Integer id;
    private String name;
    private Integer age;
    private String email;
}

3）DAO接口:接口抽象：BaseDao

//BaseDao
public interface BaseDao<T> {
    List<T> getAll();
    void insert(T t);
}

//UserDao
@Repository
public interface UserDao extends BaseDao<User> {
}

4）Mapper配置文件

<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.icucoder.learn.dao.UserDao">
    <select id="getAll" resultType="user">
        select id, name, age, email
        from user;
    </select>
    <insert id="insert" parameterType="user">
        insert into user
        values (#{id}, #{name}, #{age}, #{email});
    </insert>

</mapper>

5）Service接口

public interface UserService {
    List<User> getAll();
    void insert(User t);
}

6）Service接口实现类

@Service
@Transactional
public class UserServiceImpl implements UserService {
    @Autowired
    UserDao userDao;

    @Override
    public List<User> getAll() {
        return userDao.getAll();
    }

    @Override
    public void insert(User user) {
        System.out.println("insert success");
        userDao.insert(user);
        int i =1/0;
    }
}

7）配置相关属性

（1）配置dao扫描位置

在入口类上加上注解：@MapperScan("com.icucoder.learn.dao")//指定dao接口扫描位置

@SpringBootApplication
@MapperScan("com.icucoder.learn.dao")//指定dao接口扫描位置
public class LearnApplication {

    public static void main(String[] args) {
        SpringApplication.run(LearnApplication.class, args);
    }

}

（2）在application.properties中配置数据源和Mapper文件位置

#数据源
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/springboot?characterEncoding=UTF-8&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=xroot
#Mapper文件位置
mybatis.mapper-locations=classpath:mapper/*.xml
mybatis.type-aliases-package=com.icucoder.learn.entity

8）编写Controller测试

@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    UserService userService;

    @RequestMapping("/all")
    public List<User> all() {
        return userService.getAll();
    }

    @RequestMapping("/insert")
    public String insertOne() {
        User user = new User(7, "mayun", 29, "admin@qq.com");
        userService.insert(user);
        return "insert success";
    }
}

9）服务器附属并访问测试

http://127.0.0.1:8080/user/all