一，知识点总结
1，扫描配置注解的使用
@EnableAutoConfiguration//**自动配置，相当于写了spring配置文件**
@MapperScan(basePackages = "com.dao")//**自动扫描mapper包**
@ComponentScan(basePackages = {"com.controller","com.exception","com.service"})**//自动扫描包下注解**
public class App {
public static void main(String[] args) {
SpringApplication.run(App.class,args);
}
}
以上三个注解多用于APP.java中
2，dao层mapper接口中注解的使用
例句：
public interface UserMapper {
@Insert("insert into user (username,pwd) values(#{username},#{pwd})")
public int save(@Param("username") String username, @Param("pwd") String pwd);
@Select("select * from user where username=#{username}")
public User fintByUsername(@Param("username")String username);
}
二，结构及代码
1，pom.xml
` <dependencies>
<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java 数据库-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/org.mybatis.spring.boot/mybatis-spring-boot-starter -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.0</version>
</dependency>
</dependencies>
2,dao层
(1)通过注解实现
public interface UserMapper {
@Insert("insert into user (username,pwd) values(#{username},#{pwd})")
public int save(@Param("username") String username, @Param("pwd") String pwd);
@Select("select * from user where username=#{username}")
public User fintByUsername(@Param("username")String username);
}
(2)通过mapper.xml实现
<mapper namespace="com.dao.UserMapper">
<select id="fintByUsername" resultType="com.vo.User" parameterType="String">
select * from user where username=#{username}
</select>
<insert id="save" parameterType="String">
insert into user(username,pwd) values(#{param1},#{param2})
</insert>
</mapper>
3，service层
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserMapper userMapper;
@Override
public void reg(String username,String pwd) {
userMapper.save(username,pwd);
}
}
4，controller层
@RestController
@RequestMapping("/user")
public class UserController {
@Autowired
UserService userService;
@RequestMapping("/{id}")
@ResponseBody
public User UserInfor(@PathVariable Integer id){
User user=new User("qq","123");
user.setId(id);
return user;
}
@RequestMapping("/reg")
@ResponseBody
public String reg(String username,String pwd){
userService.reg(username,pwd);
return "sesses";
}
/*public static void main(String[] args) {
SpringApplication.run(UserController.class,args);
}*/
}
