文件下载feign调用-ResponseEntity＜byte[]＞

controller

@ApiOperation(value = "下载文件", notes = "下载文件", httpMethod = "GET", response = WebResult.class)
    @RequestMapping(value = "/download", method = RequestMethod.GET)
    public void downloadFile(@RequestParam(name = "id") String id,
                             @RequestParam(name = "fileExt", defaultValue = "", required = false) String fileExt,
                             @RequestParam(name = "fileName", defaultValue = "", required = false) String fileName,
                             HttpServletRequest request, HttpServletResponse response) throws Exception {
        String fileId = fileInfoService.getFileIdByMainId(id, fileExt);
        GridFSFile gfsfile = mongoDbFileService.getFSFile(fileId);
        String realFileName = gfsfile.getFilename().replace(",", "");
        if (StrUtil.isEmpty2(fileName)) {
            fileName = realFileName;
        } else {
            fileName = fileName.concat(".").concat(FileUtil.getFileExt(realFileName));
        }
        //处理中文文件名乱码
        if (request.getHeader("User-Agent").toUpperCase().contains("MSIE") ||
                request.getHeader("User-Agent").toUpperCase().contains("TRIDENT")
                || request.getHeader("User-Agent").toUpperCase().contains("EDGE")) {
            fileName = java.net.URLEncoder.encode(fileName, "UTF-8");
        } else {
            //非IE浏览器的处理：
            fileName = new String(fileName.getBytes("UTF-8"), "ISO-8859-1");
        }
        // 通知浏览器进行文件下载
        //response.setContentType(gfsfile.getContentType());
        response.setHeader("Content-Disposition", "attachment;filename=\"" + fileName + "\"");
        //gfsfile.writeTo(response.getOutputStream());
        GridFsResource gridFsResource = mongoDbFileService.convertGridFSFile2Resource(gfsfile);

        InputStream inputStream = gridFsResource.getInputStream();

        IOUtils.copy(inputStream, response.getOutputStream());
    }

fegin

@GetMapping(value = "/download")
    ResponseEntity<byte[]> downloadFile(@RequestParam(name = "id") String id,
                                        @RequestParam(name = "fileExt", defaultValue = "", required = false) String fileExt,
                                        @RequestParam(name = "fileName", defaultValue = "", required = false) String fileName);

调用方

@ApiOperation("附件下载")
    @GetMapping("/downloadAnnex")
    public ResponseEntity<byte[]> download(@NotNull(message = "文件ID不能为空") String fileId, @RequestParam(required = false,defaultValue = "") String key) {
        ResponseEntity<byte[]> responseEntity = fileSystemService.downloadFile(fileId, "", "");
        return responseEntity;
    }