今天学习了一下mybatis-plus的用法简单记录一下

1目录结构

2 导入依赖

<!--        mybatis依赖-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.1</version>
        </dependency>
<!--        支持jdbc访问数据库的依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
<!--mybatis plus的依赖-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.0.7.1</version>
        </dependency>
        

3 写dao层

//@Mapper(可以写mapper注解  也可以在启动类上面设置mapper包扫描)
public interface UserDao extends BaseMapper<User> {
}

4 写service层

4.1 写接口DemoService

public interface DemoService extends IService<User> {
    void add(User user);
}

4.2 写接口的实现类 DemoServiceImpl

@Service
//开启事务的注解
@Transactional 
public  class DemoServiceimpl extends ServiceImpl<UserDao, User> implements DemoService {
    @Resource
    private UserDao userDao;
    //新整用户
    @Override
    public void add(User user) {
        int insert = userDao.insert(user);
        System.out.println(insert);
    }

5 写entity层的实体类

@Data
@EqualsAndHashCode
public class User implements Serializable {
    @Id
    private Integer id;
    private String name;
}

6 写controller层

@RestController
public class DemoController {
    @Resource
    private DemoService demoService;

    @RequestMapping("/add")
    public void add (){
        User user = new User();
        user.setName("111");
        demoService.add(user);
    }
}

7 写config层

@Configuration
public class MybatisPlusConfig {
    /**
     * mybatis-plus SQL执行效率插件【生产环境可以关闭】
     */
    @Bean
    public PerformanceInterceptor performanceInterceptor() {
        return new PerformanceInterceptor();
    }
    /**
     * 分页插件
     */
    @Bean
    public PaginationInterceptor paginationInterceptor() {
        return new PaginationInterceptor();
    }
}

8 写启动类

@SpringBootApplication
//包扫描  扫描mapper里面的文件
@MapperScan(basePackages = {"com.example.demo.dao"})
public class DemoApplication {

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

}