spring:
  datasource:
    url: jdbc:h2:tcp://localhost/~/datajpa
    username: sa
    password:
    driver-class-name: org.h2.Driver

  jpa:
    hibernate:
      ddl-auto: create
    properties:
      hibernate:
        format_sql: true

logging.level:
    org.hibernate.SQL: debug
#    org.hibernate.type: trace

• trace 부분은 주석을 풀면 쿼리 파라미터까지 확인이 가능

@Repository
public class MemberJpaRepository {

	@PersistenceContext
	private EntityManager em;

	public Member save(Member member) {
		em.persist(member);

		return member;
	}

	public Member find(Long id) {
		return em.find(Member.class, id);
	}
}

테스트를 만들자 JUnit5로

• Junit5 에서 RunWith 안써도댐
• jupiter가 junit5이다.

@SpringBootTest
class MemberJpaRepositoryTest {

	@Autowired
	MemberJpaRepository memberJpaRepository;

	@Test
	public void testMember() {
		Member member = new Member("cmlee");
		Member savedMember = memberJpaRepository.save(member);

		Member findMember = memberJpaRepository.find(savedMember.getId());

		assertThat(findMember.getId()).isEqualTo(savedMember.getId());
		assertThat(findMember.getUsername()).isEqualTo(savedMember.getUsername());
	}
}

• 에러가 발생한다.
• JPA의 모든 데이터 변경은 트랜잭션 내에서 이뤄져야 한다.

@SpringBootTest
@Transactional
class MemberJpaRepositoryTest {

	@Autowired
	MemberJpaRepository memberJpaRepository;

	@Test
	public void testMember() {
		Member member = new Member("cmlee");
		Member savedMember = memberJpaRepository.save(member);

		Member findMember = memberJpaRepository.find(savedMember.getId());

		assertThat(findMember.getId()).isEqualTo(savedMember.getId());
		assertThat(findMember.getUsername()).isEqualTo(savedMember.getUsername());
	}
}

• org.springframework 패키지의 어노테이션을 사용하자. 더 기능이 많다.

@SpringBootTest
@Transactional
class MemberJpaRepositoryTest {

	@Autowired
	MemberJpaRepository memberJpaRepository;

	@Test
	public void testMember() {
		Member member = new Member("cmlee");
		Member savedMember = memberJpaRepository.save(member);
		Member findMember = memberJpaRepository.find(savedMember.getId());

		assertThat(findMember.getId()).isEqualTo(member.getId());
		assertThat(findMember.getUsername()).isEqualTo(member.getUsername());
		assertThat(findMember).isEqualTo(member);
	}
}

• isEqualTo는 == 비교이다.
• 같은 트랜잭션 내에서는 영속성의 참조가 같음이 보장된다. 1차 캐시
  • 트랜잭션이 다르면 물론 다른 참조일 것이다.