순수 JPA 기반 리포지토리 만들기

data-jpa/src/main/java/study/datajpa/repository/MemberJpaRepository.java

@@ -5,6 +5,8 @@
 
 import javax.persistence.EntityManager;
 import javax.persistence.PersistenceContext;
+import java.util.List;
+import java.util.Optional;
 
 @Repository
 public class MemberJpaRepository {
@@ -17,6 +19,25 @@ public Member save(Member member) {
         return member;
     }
 
+    public void delete(Member member) {
+        em.remove(member);
+    }
+
+    public List<Member> findAll() {
+        return em.createQuery("select m from Member m", Member.class)
+                .getResultList();
+    }
+
+    public Optional<Member> findById(Long id) {
+        Member member = em.find(Member.class, id);
+        return Optional.ofNullable(member);
+    }
+
+    public long count() {
+        return em.createQuery("select count(m) from Member m", Long.class)
+                .getSingleResult();
+    }
+
     public Member find(Long id) {
         return em.find(Member.class, id);
     }

data-jpa/src/main/java/study/datajpa/repository/TeamJpaRepository.java

@@ -0,0 +1,40 @@
+package study.datajpa.repository;
+
+import org.springframework.stereotype.Repository;
+import study.datajpa.entity.Team;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+import java.util.List;
+import java.util.Optional;
+
+@Repository
+public class TeamJpaRepository {
+
+    @PersistenceContext
+    private EntityManager em;
+
+    public Team save(Team team) {
+        em.persist(team);
+        return team;
+    }
+
+    public void delete(Team team) {
+        em.remove(team);
+    }
+
+    public List<Team> findAll() {
+        return em.createQuery("select t from Team t", Team.class)
+                .getResultList();
+    }
+
+    public Optional<Team> findById(Long id) {
+        Team team = em.find(Team.class, id);
+        return Optional.ofNullable(team);
+    }
+
+    public long count() {
+        return em.createQuery("select count(t) from Team t", Long.class)
+                .getSingleResult();
+    }
+}

data-jpa/src/test/java/study/datajpa/repository/MemberJpaRepositoryTest.java

@@ -8,6 +8,8 @@
 import org.springframework.transaction.annotation.Transactional;
 import study.datajpa.entity.Member;
 
+import java.util.List;
+
 import static org.assertj.core.api.Assertions.*;
 
 @SpringBootTest
@@ -29,4 +31,33 @@ public void testMember() {
         assertThat(findMember.getUsername()).isEqualTo(member.getUsername());
         assertThat(findMember).isEqualTo(member);   //findMember == member
     }
+
+    @Test
+    public void basicCRUD() {
+        Member member1 = new Member("member1");
+        Member member2 = new Member("member2");
+        memberJpaRepository.save(member1);
+        memberJpaRepository.save(member2);
+
+        //단건 조회 검증
+        Member findMember1 = memberJpaRepository.findById(member1.getId()).get();
+        Member findMember2 = memberJpaRepository.findById(member2.getId()).get();
+        assertThat(findMember1).isEqualTo(member1);
+        assertThat(findMember2).isEqualTo(member2);
+
+        //리스트 조회 검증
+        List<Member> all = memberJpaRepository.findAll();
+        assertThat(all.size()).isEqualTo(2);
+
+        //카운트 검증
+        long count = memberJpaRepository.count();
+        assertThat(count).isEqualTo(2);
+
+        //삭제 검증
+        memberJpaRepository.delete(member1);
+        memberJpaRepository.delete(member2);
+
+        long deletedCount = memberJpaRepository.count();
+        assertThat(deletedCount).isEqualTo(0);
+    }
 }