通过年龄找人：
1.添加springboot需要用的东西，web，mysql，mybatis，jdbc
2.创建包controller，service，dao，domain，配置文件中添加mapper文件，再此包下创建一个映射文件
3.写代码，首先domain层
@Data
public class people {
private String name;
private Integer age;
}
service层：
public interface PeopleService {
people findByage(Integer age);
}
@Service
public class PeopleServiceImpl implements PeopleService {
@Autowired
PeopleDao peopleDao;
@Override
public people findByage(Integer age) {
return peopleDao.findByAge(age);
}
}
dao层：
public interface PeopleDao {
people findByAge(@Param("age") Integer age);
}
controller层：
@RestController
public class PeopleConroller {
@Autowired
PeopleService peopleService;
@RequestMapping("/findPeople")
public people findOnePeople( Integer age) {
return peopleService.findByage(age);
}
}
映射文件：
<mapper namespace="com.shuai.springmybatis.dao.PeopleDao">
<select id="findByAge" resultType="people" parameterType="java.lang.Integer">
select * from people where age=#{age};
</select>
</mapper>
配置文件：
## 数据源配置
spring.datasource.url=jdbc:mysql://localhost:3306/mypeople?serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=3041
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
## Mybatis 配置
mybatis.typeAliasesPackage=com.shuai.springmybatis.domain
mybatis.mapperLocations=classpath:mapper/*.xml
启动类：
@SpringBootApplication
@MapperScan("com.shuai.springmybatis.dao")
public class SpringMybatisApplication {
public static void main(String[] args) {
SpringApplication.run(SpringMybatisApplication.class, args);
}
}
xml整合需要在配置文件里配置，还需要在启动类里面添加@mapperscan注解比较麻烦
使用注解开发,配置文件，启动类里面都不需要再配置了只需要添加一个@mapper
@Mapper
public interface PeopleDao {
@Select("select * from people where age=#{age}")
people findByAge(@Param("age") Integer age);
}
