原上傳文件上傳成功后.apk格式就變成.vnd.android.package-archive
原上傳：

@PostMapping("/upload")
    public AjaxResult uploadFile(MultipartFile file) throws IOException {
        if (!file.isEmpty()) {

            if (file != null && file.getOriginalFilename() != null) {
                //文件類型
                String contentType = file.getContentType();
                //獲取文件名稱
                String ext = contentType.substring(contentType.lastIndexOf("/") + 1, contentType.length());
                FileDTO input = new FileDTO();
                input.setName(file.getOriginalFilename());
                input.setStream(file.getInputStream());
                input.setExt(ext);
                String url = UploadFactory.uploadFile(input,"file");
                AjaxResult ajax = AjaxResult.success();
                ajax.put("url", url);
                return ajax;
            }
        }
            return AjaxResult.error("上傳圖片異常，請聯系管理員");
    }

新上傳：

@PostMapping("/apk/upload")
    public AjaxResult uploadApkFile(MultipartFile file) throws IOException {
        if (!file.isEmpty()) {

            if (file != null && file.getOriginalFilename() != null) {
                //文件類型
                String contentType = file.getOriginalFilename();
                //獲取文件名稱
                String ext = contentType.substring(contentType.lastIndexOf(".") + 1, contentType.length());
                FileDTO input = new FileDTO();
                input.setName(file.getOriginalFilename());
                input.setStream(file.getInputStream());
                input.setExt(ext);
                String url = UploadFactory.uploadFile(input,"apk");
                AjaxResult ajax = AjaxResult.success();
                ajax.put("url", url);
                return ajax;
            }
        }
        return AjaxResult.error("上傳圖片異常，請聯系管理員");
    }