순수 JPA 리포지토리와 Querydsl
- JPAQueryFactory Bean 등록
@SpringBootApplication
public class QuerydslApplication {
public static void main(String[] args) {
SpringApplication.run(QuerydslApplication.class, args);
}
@Bean
JPAQueryFactory jpaQueryFactory(EntityManager em) {
return new JPAQueryFactory(em);
}
}
JPAQueryFactory는 엔티티 매니저에 의존하고 엔티티 매니저의 동시성 문제는 걱정하지 않아도 된다
여기서 스프링이 주입해주는 엔티티 매니저는 실제 동작 시점에 진짜 엔티티 매니저를 찾아주는 프록시용 가짜 엔티티 매니저이다
이 가짜 엔티티 매니저는 실제 사용 시점에 트랜잭션 단위로 실제 엔티티 매니저(영속성 컨텍스트)를 할당(라우팅)해준다
더 자세한 내용은 자바 ORM 표준 JPA 책 13.1 트랜잭션 범위의 영속성 컨텍스트를 참고하자
@Repository
@RequiredArgsConstructor
public class MemberJpaRepository {
private final EntityManager em;
private final JPAQueryFactory queryFactory;
public void save(Member member) {
em.persist(member);
}
public Optional<Member> findById(Long id) {
Member findMember = em.find(Member.class, id);
return Optional.ofNullable(findMember);
}
public List<Member> findAll() {
return em.createQuery("select m from Member m", Member.class)
.getResultList();
}
public List<Member> findAll_Querydsl() {
return queryFactory
.selectFrom(member)
.fetch();
}
public List<Member> findByUsername(String username) {
return em.createQuery("select m from Member m where m.username = :username", Member.class)
.setParameter("username", username)
.getResultList();
}
public List<Member> findByUsername_Querydsl(String username) {
return queryFactory
.selectFrom(member)
.where(member.username.eq(username))
.fetch();
}
}
@SpringBootTest
@Transactional
class MemberJpaRepositoryTest {
@PersistenceContext
EntityManager em;
@Autowired
MemberJpaRepository memberJpaRepository;
@Test
public void basicQuerydslTest() {
Member member = new Member("member1", 10);
memberJpaRepository.save(member);
Member findMember = memberJpaRepository.findById(member.getId()).get();
assertThat(findMember).isEqualTo(member);
List<Member> result1 = memberJpaRepository.findAll_Querydsl();
assertThat(result1).containsExactly(member);
List<Member> result2 = memberJpaRepository.findByUsername_Querydsl("member1");
assertThat(result2).containsExactly(member);
}
}
동적 쿼리와 성능 최적화 조회 - Builder 사용
@Data
public class MemberTeamDto {
private Long memberId;
private String username;
private int age;
private Long teamId;
private String teamName;
@QueryProjection
public MemberTeamDto(Long memberId, String username, int age, Long teamId, String teamName) {
this.memberId = memberId;
this.username = username;
this.age = age;
this.teamId = teamId;
this.teamName = teamName;
}
}
@Data
public class MemberSearchCondition {
//회원명, 팀명, 나이(ageGoe, ageLoe)
private String username;
private String teamName;
private Integer ageGoe;
private Integer ageLoe;
}
@Repository
@RequiredArgsConstructor
public class MemberJpaRepository {
private final EntityManager em;
private final JPAQueryFactory queryFactory;
...
public List<MemberTeamDto> searchByBuilder(MemberSearchCondition condition) {
BooleanBuilder builder = new BooleanBuilder();
if (hasText(condition.getUsername())) {
builder.and(member.username.eq(condition.getUsername()));
}
if (hasText(condition.getTeamName())) {
builder.and(team.name.eq(condition.getTeamName()));
}
if (condition.getAgeGoe() != null) {
builder.and(member.age.goe(condition.getAgeGoe()));
}
if (condition.getAgeLoe() != null) {
builder.and(member.age.loe(condition.getAgeLoe()));
}
return queryFactory
.select(new QMemberTeamDto(
member.id,
member.username,
member.age,
team.id,
team.name
)
)
.from(member)
.leftJoin(member.team, team)
.where(builder)
.fetch();
}
}
@SpringBootTest
@Transactional
class MemberJpaRepositoryTest {
@PersistenceContext
EntityManager em;
@Autowired
MemberJpaRepository memberJpaRepository;
...
@Test
public void searchTest() {
Team teamA = new Team("teamA");
Team teamB = new Team("teamB");
em.persist(teamA);
em.persist(teamB);
Member member1 = new Member("member1", 10, teamA);
Member member2 = new Member("member2", 20, teamA);
Member member3 = new Member("member3", 30, teamB);
Member member4 = new Member("member4", 40, teamB);
em.persist(member1);
em.persist(member2);
em.persist(member3);
em.persist(member4);
MemberSearchCondition condition = new MemberSearchCondition();
condition.setAgeGoe(35);
condition.setAgeLoe(40);
condition.setTeamName("teamB");
List<MemberTeamDto> result = memberJpaRepository.searchByBuilder(condition);
assertThat(result).extracting("username").containsExactly("member4");
}
}
동적 쿼리와 성능 최적화 조회 - Where절 파라미터 사용
@Repository
@RequiredArgsConstructor
public class MemberJpaRepository {
private final EntityManager em;
private final JPAQueryFactory queryFactory;
...
public List<MemberTeamDto> search(MemberSearchCondition condition) {
return queryFactory
.select(new QMemberTeamDto(
member.id,
member.username,
member.age,
team.id,
team.name)
)
.from(member)
.leftJoin(member.team, team)
.where(
usernameEq(condition.getUsername()),
teamNameEq(condition.getTeamName()),
ageGoe(condition.getAgeGoe()),
ageLoe(condition.getAgeLoe())
)
.fetch();
}
private BooleanExpression usernameEq(String username) {
return hasText(username) ? member.username.eq(username) : null;
}
private BooleanExpression teamNameEq(String teamName) {
return hasText(teamName) ? team.name.eq(teamName) : null;
}
private BooleanExpression ageGoe(Integer ageGoe) {
return ageGoe != null ? member.age.goe(ageGoe) : null;
}
private BooleanExpression ageLoe(Integer ageLoe) {
return ageLoe != null ? member.age.loe(ageLoe) : null;
}
public List<Member> searchMember(MemberSearchCondition condition) {
return queryFactory
.select(member)
.from(member)
.leftJoin(member.team, team)
.where(
usernameEq(condition.getUsername()),
teamNameEq(condition.getTeamName()),
ageBetween(condition.getAgeLoe(), condition.getAgeGoe())
)
.fetch();
}
private BooleanExpression ageBetween(int ageLoe, int ageGoe) {
return ageLoe(ageLoe).and(ageGoe(ageGoe));
}
}
@SpringBootTest
@Transactional
class MemberJpaRepositoryTest {
@PersistenceContext
EntityManager em;
@Autowired
MemberJpaRepository memberJpaRepository;
...
@Test
public void searchTest() {
Team teamA = new Team("teamA");
Team teamB = new Team("teamB");
em.persist(teamA);
em.persist(teamB);
Member member1 = new Member("member1", 10, teamA);
Member member2 = new Member("member2", 20, teamA);
Member member3 = new Member("member3", 30, teamB);
Member member4 = new Member("member4", 40, teamB);
em.persist(member1);
em.persist(member2);
em.persist(member3);
em.persist(member4);
MemberSearchCondition condition = new MemberSearchCondition();
condition.setAgeGoe(35);
condition.setAgeLoe(40);
condition.setTeamName("teamB");
List<MemberTeamDto> result = memberJpaRepository.search(condition);
assertThat(result).extracting("username").containsExactly("member4");
}
}
조회 API 컨트롤러 개발
src/main/resources/application.yml
spring:
profiles:
active: local
...
src/test/resources/application.yml- main 소스코드와 테스트 소스 코드 실행시 프로파일을 분리할 수 있다
spring:
profiles:
active: test
...
- 샘플 데이터 추가하기
@Profile("local")
@Component
@RequiredArgsConstructor
public class InitMember {
private final InitMemberService initMemberService;
@PostConstruct // 생명주기 때문에 @Transactional와 같이 사용하지 못한다
public void init() {
initMemberService.init();
}
@Component
static class InitMemberService {
@PersistenceContext
private EntityManager em;
@Transactional // 생명주기 때문에 @PostConstruct와 같이 사용하지 못한다
public void init() {
Team teamA = new Team("teamA");
Team teamB = new Team("teamB");
em.persist(teamA);
em.persist(teamB);
for (int i = 0; i < 100; ++i) {
Team selectedTeam = i % 2 == 0 ? teamA : teamB;
em.persist(new Member("member" + i, i, selectedTeam));
}
}
}
}
@RestController
@RequiredArgsConstructor
public class MemberController {
private final MemberJpaRepository memberJpaRepository;
@GetMapping("/v1/members")
public List<MemberTeamDto> searchMemberV1(MemberSearchCondition condition) {
return memberJpaRepository.search(condition);
}
}
예제 실행(postman)
참고 자료