Member 생성, 조회, 수정 구현

src/main/java/com/gdgoc/study_group/member/application/MemberService.java

@@ -0,0 +1,61 @@
+package com.gdgoc.study_group.member.application;
+
+import com.gdgoc.study_group.member.dao.MemberRepository;
+import com.gdgoc.study_group.member.domain.Member;
+import com.gdgoc.study_group.member.dto.request.MemberCreateRequestDto;
+import com.gdgoc.study_group.member.dto.request.MemberUpdateRequestDto;
+import java.util.NoSuchElementException;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+@RequiredArgsConstructor
+public class MemberService {
+
+  private final MemberRepository memberRepository;
+
+  /**
+   * 새 멤버를 생성합니다.
+   *
+   * @param request 새로 만들 멤버 정보
+   * @return Member 형태로 반환
+   */
+  public Member createMember(MemberCreateRequestDto request) {
+
+    Member newMember =
+        Member.builder()
+            .name(request.getName())
+            .github(request.getGithub())
+            .studentNumber(request.getStudentNumber())
+            .build();
+
+    return memberRepository.save(newMember);
+  }
+
+  /**
+   * 멤버를 조회합니다.
+   *
+   * @param memberId 멤버를 조회할 정보
+   * @return Member 형태로 반환
+   */
+  public Member getMember(Long memberId) {
+    return memberRepository
+        .findById(memberId)
+        .orElseThrow(() -> new NoSuchElementException("member not found"));
+  }
+
+  /**
+   * 멤버가 정보를 수정합니다.
+   *
+   * @param memberId 멤버를 조회할 정보
+   * @param request 수정할 정보
+   */
+  @Transactional
+  public void updateMember(Long memberId, MemberUpdateRequestDto request) {
+
+    Member member = getMember(memberId);
+
+    member.updateMember(request.getName(), request.getGithub(), request.getStudentNumber());
+  }
+}