JPA做分頁查詢

JpaRepository有分頁查詢的函數，按API要求傳遞對應參數即可分頁查詢。

分頁查詢需要傳入分頁對象Pageable pageable = PageRequest.of(pageNum, pageSize);

關鍵代碼如下：

//Repository
@Repository()
public interface ApplicationRepository extends JpaRepository<ApplicationDTO, Integer>{
    Page<ApplicationDTO> findAll(Pageable pageable);
}

//Service
@Service
public ApplicationService {
    @Autowired
    private ApplicationRepository applicationRepository;
    public Page<ApplicationDTO> getApps(Integer pageNum, Integer pageSize) {
        if(Objects.isNull(pageNum)){
            pageNum = 0;
        }
        if(Objects.isNull(pageSize)){
            pageSize = 10;
        }
        Pageable pageable = PageRequest.of(pageNum, pageSize);
        return applicationRepository.findAll(state,pageable);
    }
}