java返回文件流和返回Json混用_废材是怎么养成的_java 返回文件

网络投稿 02-07 686

遇到一个需求，前端上传Excel文件，后端校验校验不通过直接返回并下载带有失败信息的Excel文件，如果是其他情况则返回相应的Json提示信息。

前后端用于处理Java上传文件后成功和失败返回Json信息，校验失败放回文件流并下载。

一个接口兼顾Json返回和文件流返回

1、vue前端请求处理：

// 封装axios的下载数据流转换成excel export function DownLoadToExcel(url, data = {}, fileName) { fileName = fileName + '.xls' return new Promise((resolve, reject) => { axios .post(url, data, { ? // 必须设置不然Excel下载后打不开 responseType: 'blob', dataType: 'json', headers: { 'Content-Type': 'application/json; application/vnd.ms-excel' } }) .then(response => { resolve(response) }) .catch(error => { console.log(error) reject(error) }) }) }

2、前端上传附件方法处理：

uploads() { let formdata = new FormData() formdata.append('file', this.file) this.loadingStatus = true this.$http.DownLoadToExcel(this.uploadUrl, formdata, this.file.name).then(res => { const resData = res.data let that = this // 处理返回是Json的数据 if (resData.type === 'application/json') { // 说明是普通对象数据，读取信息 const fileReader = new FileReader() fileReader.onloadend = () => { debugger try { const jsonData = JSON.parse(fileReader.result) // 后台信息 console.log(jsonData) debugger if (jsonData.code === 200) { debugger that.tips.class = this.tips.successClass that.tips.message = '文件导入成功！' that.$emit('fileUploadSuccess') } else { that.tips.class = that.tips.failClass that.tips.message = jsonData.message } } catch (err) { console.log(err) } } fileReader.readAsText(res.data) } else { // 校验错误时直接下载校验错误Excel const blob = new Blob([res.data], { type: 'application/vnd.ms-excel' }) if ('download' in document.createElement('a')) { // 非IE下载 const elink = document.createElement('a') elink.download = this.file.name elink.style.display = 'none' elink.href = URL.createObjectURL(blob) document.body.appendChild(elink) elink.click() URL.revokeObjectURL(elink.href) document.body.removeChild(elink) } else { // IE10+下载 navigator.msSaveBlob(blob, this.file.name) } this.file = null } }).catch(err => { console.log(err) }) }

3、后端

@PostMapping("wikipediaImportData") @ApiOperation("百科excel导入") JsonResponse<Map<String, Object>> wikipediaExportData(@RequestParam("file") MultipartFile file, HttpServletResponse response){ JsonResponse<Map<String, Object>> jonResponse = JsonResponse.ok(); String fileName = file.getOriginalFilename(); // 校验格式 if (!(fileName != null && (fileName.endsWith(".xlsx") || fileName.endsWith(".xls")))) { jonResponse.setCode(RequestStatus.HEAD_FAILED.code); jonResponse.setMessage(RequestStatus.HEAD_FAILED.message); jonResponse.setSuccess(false); } / 这里得设置返回请求信息 response.setContentType("application/json;charset=UTF-8"); response.setCharacterEncoding("UTF-8"); ExcelReader reader = ExcelFactory.readBuilder() .head(WikipediaExcelDTO.class) .build(); try { AnalyzedResult<WikipediaExcelDTO> result = reader.read(file.getInputStream()); switch (result.getRStatus()) { case SUCCESS: List<WikipediaExcelDTO> dataList = result.getDataList(); List<BaseResourceDTO> baseResourceDTOList = dataList.stream().map(data -> { BaseResourceDTO resourceDTO = new BaseResourceDTO(); BeanUtils.copyProperties(data, resourceDTO); return resourceDTO; }).collect(Collectors.toList()); indexService.syncResource(baseResourceDTOList); jonResponse.setCode(RequestStatus.OK.code); jonResponse.setMessage(RequestStatus.OK.message); jonResponse.setSuccess(true); break; case DATA_FAILED: // 数据校验出错时候直接返回错误文件流 response.setContentType("application/vnd.ms-excel"); response.setCharacterEncoding("UTF-8"); try { response.setHeader("Content-disposition", "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8") + ".xlsx"); } catch (UnsupportedEncodingException var3) { response.setHeader("Content-disposition", "attachment;filename=" + fileName + ".xlsx"); } // ExcelUtil.writeExcelResponseHeader(response, fileName); ExcelFactory.errorExportBuilder() .cellList(result.getCellList()) .head(WikipediaExcelDTO.class) .build() .export(response.getOutputStream()); jonResponse.setCode(RequestStatus.DATA_FAILED.code); jonResponse.setMessage(RequestStatus.DATA_FAILED.message); jonResponse.setSuccess(false); break; case HEAD_FAILED: jonResponse.setCode(RequestStatus.HEAD_FAILED.code); jonResponse.setMessage(RequestStatus.HEAD_FAILED.message); jonResponse.setSuccess(false); break; case ERROR: jonResponse.setCode(RequestStatus.ERROR.code); jonResponse.setMessage(RequestStatus.ERROR.message); jonResponse.setSuccess(false); break; default: jonResponse.setCode(result.getRStatus().getCode()); jonResponse.setMessage(result.getRStatus().getMessage()); jonResponse.setSuccess(false); break; } } catch (Exception e) { log.error("百科导入文件错误"); jonResponse.setCode(RequestStatus.ERROR.code); jonResponse.setMessage(RequestStatus.ERROR.message); jonResponse.setSuccess(false); } return jonResponse; }

?返回失败的Json

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