docs: public static <E, T> PageDto createPageDto(final Page<? extends E> page,
                                                 final PageEntryTransformer<T, E> transformer) {
          if (page == null) {
              return null;
          }
          if (page instanceof PageDto && transformer == null) {
              return (PageDto) page;
          }
          final PageRequestDto pageRequestDto = createPageRequestDto(page.getPageRequest());
          if (transformer == null) {
              return new PageDto(page.getEntries(), pageRequestDto, page.getTotalSize());
          }
          final List<T> entries = new ArrayList<>();
          for (E e : page.getEntries()) {
              entries.add(transformer.transform(e));
          }
          final PageDto pageDto = new PageDto();
          pageDto.setEntries(CastUtils.cast(entries));
          pageDto.setPageRequest(pageRequestDto);
          pageDto.setTotalSize(page.getTotalSize());
          return pageDto;
      }