2023년 1월 6일

JPA Specification

JpaSpecificationExecutor

// repositories/PlaceRepository.java

public interface PlaceRepository
    extends JpaRepository<Place, Long>, JpaSpecificationExecutor<Place> {
    Optional<Place> findByInformationName(String placeName);
}

 

 

Specification 객체

// specifications/PlaceSpecification.java

public class PlaceSpecification {
    public static Specification<Place> likeInformationName(
        String informationName
    ) {
        return new Specification<Place>() {
            @Override
            public Predicate toPredicate(Root<Place> root,
                                         CriteriaQuery<?> query,
                                         CriteriaBuilder criteriaBuilder) {
                return criteriaBuilder.like(
                    root.get("information")
                    	.get("name"),
                    "%" + informationName + "%");
            }
        };
        
        // return (root, query, criteriaBuilder) -> criteriaBuilder.like(
        //     root.get("information")
        //         .get("name"),
         //    "%" + keyword + "%");
    }
}

 

Service

// services/SearchPlacesService.java

public class SearchPlacesService {
    private final PlaceRepository placeRepository;

    public SearchPlacesService(PlaceRepository placeRepository) {
        this.placeRepository = placeRepository;
    }

    public PlaceSearchResultsDto searchPlaces(String keyword) {
        Specification<Place> specification
            = Specification.where(PlaceSpecification.likeInformationName(keyword));

        List<PlaceSearchResultDto> placeSearchResultDtos
            = placeRepository.findAll(specification)
            .stream()
            .map(Place::toSearchResultDto)
            .toList();

        return new PlaceSearchResultsDto(placeSearchResultDtos);
    }
}

 

References

- root.get: https://dev-setung.tistory.com/20

 

 

 

 

array.splice() vs array.slice()

splice는 원본 배열을 변경 >> 원본 배열에 가변

slice는 새로운 배열을 생성해 변경 >> 원본 배열은 불변

아직 직접 검증하지 않음