jpashop : member service

jpashop/src/main/java/com/example/jpashop/repository/MemberRepository.java

@@ -1,6 +1,7 @@
 package com.example.jpashop.repository;
 
 import com.example.jpashop.domain.Member;
+import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Repository;
 
 import javax.persistence.EntityManager;
@@ -8,10 +9,15 @@ import javax.persistence.PersistenceContext;
 import java.util.List;
 
 @Repository
+@RequiredArgsConstructor
 public class MemberRepository {
 
-    @PersistenceContext
-    private EntityManager em;
+//    Spring data JPA 가 @Autowired 로 주입을 해주기 때문에 @RequiredArgsConstructor 사용가능 (생성자 주입)
+//    기본적으로는 @PersistenceContext 사용
+//    @PersistenceContext
+//    private EntityManager em;
+
+    private final EntityManager em;
 
     public void save(Member member){
         em.persist(member);

jpashop/src/main/java/com/example/jpashop/service/MemberService.java

@@ -0,0 +1,50 @@
+package com.example.jpashop.service;
+
+import com.example.jpashop.domain.Member;
+import com.example.jpashop.repository.MemberRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+
+@Service
+@Transactional(readOnly = true) // readOnly = true -> 조회의 경우 성능 최적화
+@RequiredArgsConstructor
+public class MemberService {
+
+    private final MemberRepository memberRepository;
+
+//    @Autowired
+//    public MemberService(MemberRepository memberRepository) {
+//        this.memberRepository = memberRepository;
+//    }
+
+    /**
+     *  회원 가입
+     */
+    @Transactional
+    public Long join(Member member) {
+        validateDuplicateMember(member); // 중복 회원 검증
+        memberRepository.save(member) ;
+        return member.getId();
+    }
+
+    private void validateDuplicateMember(Member member) {
+        // Exception
+        List<Member> findMembers = memberRepository.findByName(member.getName());
+        if (!findMembers.isEmpty()) {
+            throw new IllegalStateException("이미 존재하는 회원입니다.");
+        }
+    }
+
+    // 전체회원 조회
+    public List<Member> findMembers() {
+        return memberRepository.findAll();
+    }
+
+    public Member findOne(Long memberId) {
+        return memberRepository.findOne(memberId);
+    }
+}