JPA Entity > Repository

Entity

@Getter
@Entity
@NoArgsConstructor(access = AccessLevel.PROTECTED)
@AllArgsConstructor
@Table(name = "info")

public class Info {
  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  @Column(name = "info_seq", length = 11)
  private Integer infoSeq;

  @Column(name = "a")
  private String a;

  @Column(name = "b")
  private String b;

  @Column(name = "c")
  private String c;

  @Column(name = "d")
  private String d;
}

 

DTO

@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
public class InfoDTO implements Serializable {

  private Integer infoSeq;
  private String a;
  private String b;
  private String c;
  private String d;

  // 모든 변수 사용 시 @AllArgsConstructor 삭제
  @QueryProjection
  public InfoDTO(Integer infoSeq, String a, String b, String c) {
    this.infoSeq = infoSeq;
    this.a = a;
    this.b = b;
    this.c = c;
  }
}

 

Repository

방법1.

@Repository
public interface InfoRepository extends JpaRepository<Info, Integer>, InfoRepositoryCustom {

}

public interface InfoRepositoryCustom {
  InfoDTO findInfoByA(String A);
}

public class InfoRepositoryCustomImpl implements InfoRepositoryCustom {
  private final JPAQueryFactory jpaQueryFactory;

  public InfoRepositoryCustomImpl(EntityManager em) {
    this.jpaQueryFactory = new JPAQueryFactory(em);
  }

  public InfoDTO findInfoByA(String a) {
    return jpaQueryFactory
        .select(new QInfoDTO(info.infoSeq, info.a, info.b, info.c))
        .from(info)
        .where(info.a.eq(a))
        .fetchOne();
  }
}

 

방법2.

@Repository
public interface InfoRepository extends JpaRepository<Info, Integer> {

}

@Repository
public class InfoQueryRepository {
  private final JPAQueryFactory jpaQueryFactory;

  public InfoQueryRepository(EntityManager em) {
    this.jpaQueryFactory = new JPAQueryFactory(em);
  }

  public InfoDTO findInfoByA(String a) {
    return jpaQueryFactory
        .select(new QInfoDTO(info.infoSeq, info.a, info.b, info.c))
        .from(info)
        .where(info.a.eq(a))
        .fetchOne();
  }
}