1. 문제

2. 새 도구

3. 코드 — v2 minimal Member 형태

// com/smhrd/domain/Member.java
@Data @AllArgsConstructor @NoArgsConstructor
public class Member {
    private String id;
    private String pwd;
}

// com/smhrd/mapper/MemberMapper.java
@Mapper public interface MemberMapper {
    Member selectOne(String id);
}

<!-- com/smhrd/mapper/MemberMapper.xml -->
<mapper namespace="com.smhrd.mapper.MemberMapper">
  <select id="selectOne"
          parameterType="string"
          resultType="com.smhrd.domain.Member">
    SELECT id, pwd FROM mymember WHERE id = #{id}
  </select>
</mapper>

// com/smhrd/service/MemberService.java
@Service
public class MemberService {
    @Autowired MemberMapper mapper;
    public Member find(String id) { return mapper.selectOne(id); }
}

// com/smhrd/controller/MemberController.java
@Controller
public class MemberController {
    @Autowired MemberService service;
    @GetMapping("/member/view")
    public String view(@RequestParam String id, Model model) {
        model.addAttribute("member", service.find(id));
        return "member/view";
    }
}

<!-- view.jsp -->
<h1>${member.id}</h1>
<p>${member.pwd}</p>

4. 정리

• 브라우저 ↔ Controller ↔ Service ↔ Mapper ↔ DB 가 모두 연결
• v0.5 의 하드코딩 자리에 DB 호출이 들어감
• v1 — 우리 프로젝트의 진짜 시작

5. Before / After