[Week9][Chap4] Feat : 엔티티 그래프(#107)

최송희/data-jpa/src/main/java/study/datajpa/repository/MemberRepository.java

@@ -2,6 +2,7 @@
 
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
+import org.springframework.data.jpa.repository.EntityGraph;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Modifying;
 import org.springframework.data.jpa.repository.Query;
@@ -37,4 +38,8 @@ public interface MemberRepository extends JpaRepository<Member, Long> {
     @Modifying(clearAutomatically = true)
     @Query("update Member m set m.age = m.age+1 where m.age>= :age")
     int bulkAgePlus(@Param("age")int age);
+
+    @Override
+    @EntityGraph(attributePaths = {"team"})
+    List<Member> findAll();
 }

최송희/data-jpa/src/test/java/study/datajpa/repository/MemberRepositoryTest.java

@@ -191,4 +191,31 @@ public void bulkUpdate(){
 
         assertThat(resultCount).isEqualTo(3);
     }
+
+    @Test
+    public void findMemberLazy(){
+        //given
+        //member1->teamA참조
+        //member2->teamB참조
+
+        Team teamA = new Team("teamA");
+        Team teamB=  new Team("teamB");
+        teamRepository.save(teamA);
+        teamRepository.save(teamB);
+
+        Member member1 = new Member("member1", 10, teamA);
+        Member member2 = new Member("member2", 20, teamB);
+        memberRepository.save(member1);
+        memberRepository.save(member2);
+
+        entityManager.flush();
+        entityManager.clear();
+
+        List<Member> members = memberRepository.findAll();
+        for (Member member : members) {
+            System.out.println("member = "+member.getUsername());
+            System.out.println("member.team = "+member.getTeam().getName());
+        }
+
+    }
 }