Java Code Examples for org.springframework.data.domain.Page#getSize()

/**
 * Creates a list of {@link ProxyActionStatus} for presentation layer from
 * page of {@link ActionStatus}.
 *
 * @param actionBeans
 *            page of {@link ActionStatus}
 * @return list of {@link ProxyActionStatus}
 */
private List<ProxyMessage> createProxyMessages(final Page<String> messages) {
    final List<ProxyMessage> proxyMsgs = new ArrayList<>(messages.getNumberOfElements());

    Long idx = messages.getNumber() * ((long) messages.getSize());
    for (final String msg : messages) {
        idx++;
        final ProxyMessage proxyMsg = new ProxyMessage();
        proxyMsg.setMessage(msg);
        proxyMsg.setId(String.valueOf(idx));
        proxyMsgs.add(proxyMsg);
    }

    if (messages.getTotalElements() == 1L && StringUtils.isEmpty(proxyMsgs.get(0).getMessage())) {
        proxyMsgs.get(0).setMessage(noMessageText);
    }

    return proxyMsgs;
}
 

/**
 * Gets pageable contacts.
 *
 * @param pageable the pageable
 * @return the contact page
 */
@Transactional(readOnly = true)
public ContactsResponse getContacts(Pageable pageable) {

    Page<Contact> contactPage = contactRepository.findAllByCreatedBy(getLoggedInUsername(), pageable);

    long totalElements = contactPage.getTotalElements();
    int totalPage = contactPage.getTotalPages();
    int size = contactPage.getSize();
    int page = contactPage.getNumber();

    List<ContactResponse> contactResponseList = new ArrayList<>();
    for (Contact contact : contactPage.getContent()) {
        contactResponseList.add(buildContactResponse(contact));
    }

    return ContactsResponse.builder()
            .items(contactResponseList)
            .page(page)
            .size(size)
            .totalPages(totalPage)
            .totalElements(totalElements)
            .build();
}
 

@Override
public TagsResponse getTags(String siteId, Pageable pageable) {

    Page<Tag> tagPage = tagRepository.findAllByCreatedBy(pageable, getLoggedInUsername());

    long totalElements = tagPage.getTotalElements();
    int totalPage = tagPage.getTotalPages();
    int size = tagPage.getSize();
    int page = tagPage.getNumber();

    List<TagResponse> tagResponseList = new ArrayList<>();
    for (Tag tag : tagPage.getContent()) {

        tagResponseList.add(buildTagResponse(tag));
    }

    return TagsResponse.builder()
            .items(tagResponseList)
            .page(page)
            .size(size)
            .totalPages(totalPage)
            .totalElements(totalElements)
            .build();
}
 

@Override
public PagedResponse<PhotoResponse> getAllPhotosByAlbum(Long albumId, int page, int size) {
	AppUtils.validatePageNumberAndSize(page, size);

	Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, AppConstants.CREATED_AT);

	Page<Photo> photos = photoRepository.findByAlbumId(albumId, pageable);

	List<PhotoResponse> photoResponses = new ArrayList<>(photos.getContent().size());
	for (Photo photo : photos.getContent()) {
		photoResponses.add(new PhotoResponse(photo.getId(), photo.getTitle(), photo.getUrl(),
				photo.getThumbnailUrl(), photo.getAlbum().getId()));
	}

	return new PagedResponse<>(photoResponses, photos.getNumber(), photos.getSize(), photos.getTotalElements(),
			photos.getTotalPages(), photos.isLast());
}
 

@Override
public PagedResponse<PhotoResponse> getAllPhotos(int page, int size) {
	AppUtils.validatePageNumberAndSize(page, size);

	Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, CREATED_AT);
	Page<Photo> photos = photoRepository.findAll(pageable);

	List<PhotoResponse> photoResponses = new ArrayList<>(photos.getContent().size());
	for (Photo photo : photos.getContent()) {
		photoResponses.add(new PhotoResponse(photo.getId(), photo.getTitle(), photo.getUrl(),
				photo.getThumbnailUrl(), photo.getAlbum().getId()));
	}

	if (photos.getNumberOfElements() == 0) {
		return new PagedResponse<>(Collections.emptyList(), photos.getNumber(), photos.getSize(),
				photos.getTotalElements(), photos.getTotalPages(), photos.isLast());
	}
	return new PagedResponse<>(photoResponses, photos.getNumber(), photos.getSize(), photos.getTotalElements(),
			photos.getTotalPages(), photos.isLast());

}
 

public final Page<Target> convertToPage(Page<Source> sourcePage, Map<String, Object> parameters) {
    final List<Target> targets = new ArrayList<>(sourcePage.getContent().size());
    for (Source source : sourcePage) {
        targets.add(convert(source, parameters));
    }

    final Pageable pageable = new PageRequest(sourcePage.getNumber(), sourcePage.getSize(), sourcePage.getSort());

    return new PageImpl<>(targets, pageable, sourcePage.getTotalElements());
}
 

/**
 * @param search        是否是搜索请求
 * @param filters       通过 jqgrid search 查询，多个查询条件时，包含查询条件为 json 格式数据。_search = false 时，jqgrid 传递过来的参数没有 filters , 此时 filters 的值为 null
 * @param currentPageNo 当前页码
 * @param pageSize      页面可显示行数
 * @param sortParameter 用于排序的列名 ，启用 groups 时，此项复杂，需要特殊解析
 * @param sortDirection          排序的方式desc/asc
 * @return jqgrid 展示所需要的 json 结构，通过 spring 自动完成
 */
@RequestMapping(value = "/jqgrid-search", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
//注意 value  /jqgrid-search  ，不能为 /jqgrid-search/ ，不能多加后面的斜线
@ResponseBody
public JqgridPage jqgridSearch(
        @RequestParam("_search") Boolean search,
        @RequestParam(value = "filters", required = false) String filters,
        @RequestParam(value = "page", required = true) Integer currentPageNo,
        @RequestParam(value = "rows", required = true) Integer pageSize,
        @RequestParam(value = "sidx", required = true) String sortParameter,
        @RequestParam(value = "sord", required = true) String sortDirection, RedirectAttributes redirectAttrs, HttpServletRequest request) {


    log.info("search ={},page ={},rows ={},sord={},sidx={},filters={}", search, currentPageNo, pageSize, sortDirection, sortParameter, filters);

    /**
     * 记录集
     */
    Page<GroupEntity> pages = JpaUtils.getJqGridPage(groupRepository, currentPageNo, pageSize, SqlUtils.createOrder(sortDirection,sortParameter), filters);
    if (pages.getTotalElements() == 0)
        return new JqgridPage(pageSize, 0, 0, new ArrayList(0)); //构造空数据集，否则返回结果集 jqgird 解析会有问题


    /**
     * POJO to DTO
     * 转换原因见 service/package-info.java
     */

    DtoUtils dtoUtils = new DtoUtils();  //用法见 DTOUtils
    //    dtoUtils.addExcludes(MenuEntity.class, "parent"); //在整个转换过程中，无论哪个级联层次，只要遇到 TreeEntity 类，那么他的 parent 属性就不进行转换
    dtoUtils.addExcludes(GroupEntity.class, "users", "roles");

    JqgridPage<GroupEntity> jqPage = new JqgridPage
            (pages.getSize(), pages.getNumber(), (int) pages.getTotalElements(), dtoUtils.createDTOcopy(pages.getContent()));

    return jqPage;
}
 

@Override
public PagedResponse<Post> getPostsByCreatedBy(String username, int page, int size) {
	validatePageNumberAndSize(page, size);
	User user = userRepository.findByUsername(username)
			.orElseThrow(() -> new ResourceNotFoundException(USER, USERNAME, username));
	Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, CREATED_AT);
	Page<Post> posts = postRepository.findByCreatedBy(user.getId(), pageable);

	List<Post> content = posts.getNumberOfElements() == 0 ? Collections.emptyList() : posts.getContent();

	return new PagedResponse<>(content, posts.getNumber(), posts.getSize(), posts.getTotalElements(),
			posts.getTotalPages(), posts.isLast());
}
 

PageInfo(Page page) {
    this.totalElements = page.getTotalElements();
    this.totalPages = page.getTotalPages();
    this.numberOfElements = page.getNumberOfElements();
    this.pageNumber = page.getNumber();
    this.pageSize = page.getSize();
}
 

@PageLinks(CustomerController.class)
public CustomerListResource build(Page<Customer> page) {

    List<CustomerResource> customerList = page.getContent()
            .stream()
            .map(customer ->  customerResourceAssembler.toResource(customer))
            .collect(Collectors.toList());

    return new CustomerListResource(customerList, page.getNumber(),
            page.getSize(), page.getTotalPages(), page.getTotalElements());
}
 

public static <S, T> Page<T> mapPage(Page<S> source, Class<T> targetClass) {
    List<S> sourceList = source.getContent();

    List<T> list = new ArrayList<>();
    for (int i = 0; i < sourceList.size(); i++) {
        T target = INSTANCE.map(sourceList.get(i), targetClass);
        list.add(target);
    }

    return new PageImpl<>(list, new PageRequest(source.getNumber(), source.getSize(), source.getSort()),
            source.getTotalElements());
}
 

/**
 * 获取统一分页对象
 */
public static <M> PageInfo<M> of(Page page, Class<M> entityModelClass) {
    int records = (int) page.getTotalElements();
    int pageSize = page.getSize();
    int total = records % pageSize == 0 ? records / pageSize : records / pageSize + 1;

    PageInfo<M> pageInfo = new PageInfo<>();
    pageInfo.setPage(page.getNumber() + 1);//页码
    pageInfo.setPageSize(pageSize);//页面大小
    pageInfo.setRows(CopyUtil.copyList(page.getContent(), entityModelClass));//分页结果
    pageInfo.setRecords(records);//总记录数
    pageInfo.setTotal(total);//总页数
    return pageInfo;
}
 

/**
 * Get page of <T>.
 *
 * @param specification {@link Specification}
 * @param pageable      pageable
 * @param voType        VO of some class
 * @return page of <T>
 */
@SuppressWarnings("unchecked")
public Page getPage(Specification<T> specification, Pageable pageable, Class voType)
    throws InstantiationException, IllegalAccessException {
  Page<T> poPage = repository.findAll(specification, pageable);
  if (poPage.getSize() == 0) {
    return null;
  }
  return transformer.poPage2VO(transformer.pos2VOs(voType, poPage.getContent()),
      pageable, poPage.getTotalElements());
}
 

private Page<Violation> mapBackendToFrontendViolations(final Page<ViolationEntity> backendViolations) {
    final PageRequest currentPageRequest = new PageRequest(
            backendViolations.getNumber(),
            backendViolations.getSize(),
            backendViolations.getSort());
    return new PageImpl<>(
            backendViolations.getContent().stream().map(entityToDto::convert).collect(toList()),
            currentPageRequest,
            backendViolations.getTotalElements());
}
 

/**
 * 获取统一分页对象
 */
public static <M> PageInfo<M> of(Page page, Class<M> entityModelClass) {
    int records = (int) page.getTotalElements();
    int pageSize = page.getSize();
    int total = records % pageSize == 0 ? records / pageSize : records / pageSize + 1;

    PageInfo<M> pageInfo = new PageInfo<>();
    pageInfo.setPage(page.getNumber() + 1);//页码
    pageInfo.setPageSize(pageSize);//页面大小
    pageInfo.setRows(CopyUtil.copyList(page.getContent(), entityModelClass));//分页结果
    pageInfo.setRecords(records);//总记录数
    pageInfo.setTotal(total);//总页数
    return pageInfo;
}
 

public PlatformPageImpl(Page page) {
    super(page.getContent(),
            new PageRequest(page.getNumber(), page.getSize(), page.getSort()),
            page.getTotalElements());
    this.number = page.getNumber();
    this.size = page.getSize();
    this.totalPages = page.getTotalPages();
    this.numberOfElements = page.getNumberOfElements();
    this.totalElements = page.getTotalElements();
    this.first = page.isFirst();
    this.last = page.isLast();
    this.content = page.getContent();
    this.sort = page.getSort();
}
 

public PageResp(Page<T> page) {
	this.rows = page.getContent();
	this.page = page.getNumber() + 1;
	this.pagesize = page.getSize();
	this.total = page.getTotalElements();
}
 

@Override
public PagedResponse<AlbumResponse> getAllAlbums(int page, int size){
       AppUtils.validatePageNumberAndSize(page, size);

       Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, CREATED_AT);

       Page<Album> albums = albumRepository.findAll(pageable);

       if (albums.getNumberOfElements() == 0){
           return new PagedResponse<>(Collections.emptyList(), albums.getNumber(), albums.getSize(), albums.getTotalElements(), albums.getTotalPages(), albums.isLast());
       }
       
       List<AlbumResponse> albumResponses = Arrays.asList(modelMapper.map(albums.getContent(), AlbumResponse[].class));
       
       return new PagedResponse<>(albumResponses, albums.getNumber(), albums.getSize(), albums.getTotalElements(), albums.getTotalPages(), albums.isLast());
   }
 

@Override
public PagedResponse<Post> getPostsByTag(Long id, int page, int size) {
	AppUtils.validatePageNumberAndSize(page, size);

	Tag tag = tagRepository.findById(id).orElseThrow(() -> new ResourceNotFoundException(TAG, ID, id));

	Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, CREATED_AT);

	Page<Post> posts = postRepository.findByTags(Arrays.asList(tag), pageable);

	List<Post> content = posts.getNumberOfElements() == 0 ? Collections.emptyList() : posts.getContent();

	return new PagedResponse<>(content, posts.getNumber(), posts.getSize(), posts.getTotalElements(),
			posts.getTotalPages(), posts.isLast());
}
 

/**
 * 构建分页返回结果
 *
 * @param data
 * @param page
 * @param <T>
 * @return
 */
public static <T> PageResult<T> pageResult(List<T> data, Page page) {
    return new PageResult<>(data, page.getNumber() + 1, page.getSize(), page.getTotalElements());
}