java - 如何在 Spring RestController 中下载 excel 文件

Question

我正在使用 Apache POI 生成.xlsx文件。

我想从 Spring 控制器返回该文件。这是我到目前为止所做的：

控制器：

@RequestMapping(method = RequestMethod.GET)
    public HttpEntity<byte[]> createExcelWithTaskConfigurations(HttpServletResponse response) throws IOException {
        byte[] excelContent = excelService.createExcel();

        HttpHeaders header = new HttpHeaders();
        header.setContentType(new MediaType("application", "vnd.openxmlformats-officedocument.spreadsheetml.sheet"));
        header.set(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=my_file.xls");
        header.setContentLength(excelContent.length);

        return new HttpEntity<>(excelContent, header);
    }

是否可以从 rest 控制器返回实际的 excel 文件，以便用户可以将其下载到他的计算机上？至于现在控制器返回 byte[] 但我想返回实际文件。我怎样才能做到这一点？

标签： javaexcelspring

Answer 1

您可以使用ByteArrayResource作为文件下载。以下是您修改后的代码片段

    @GetMapping(value="/downloadTemplate")
    public HttpEntity<ByteArrayResource> createExcelWithTaskConfigurations() throws IOException {
        byte[] excelContent = excelService.createExcel();

        HttpHeaders header = new HttpHeaders();
        header.setContentType(new MediaType("application", "force-download"));
        header.set(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=my_file.xlsx");


        return new HttpEntity<>(new ByteArrayResource(excelContent), header);
    }

如果您尝试使用 apache poi 生成 excel，请在下面找到代码片段

    @GetMapping(value="/downloadTemplate")
    public ResponseEntity<ByteArrayResource> downloadTemplate() throws Exception {
        try {
            ByteArrayOutputStream stream = new ByteArrayOutputStream();
            XSSFWorkbook workbook = createWorkBook(); // creates the workbook
            HttpHeaders header = new HttpHeaders();
            header.setContentType(new MediaType("application", "force-download"));
            header.set(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=ProductTemplate.xlsx");
            workbook.write(stream);
            workbook.close();
            return new ResponseEntity<>(new ByteArrayResource(stream.toByteArray()),
                    header, HttpStatus.CREATED);
        } catch (Exception e) {
            log.error(e.getMessage());
            return new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR);
        }
    }