java.io.IOException: UT010029: Stream is closed异常分析及解决

    @Operation(summary = "下载模版")
    @GetMapping("download")
    public Result<String> download(HttpServletResponse response) {
        String fileName = "demo模版.xlsx";
        ServletOutputStream outputStream = response.getOutputStream()
        try {
            // 清空下载文件的空白行（空白行是因为有的前端代码编译后产生的）
            response.reset();
            response.setCharacterEncoding("utf-8");
            // 解决中文文件名乱码问题
            String encodedFileName = URLEncoder.encode(fileName, "UTF-8");
            response.setHeader("Content-Disposition", "attachment;filename=\"" + encodedFileName + "\";filename*=utf-8''" + encodedFileName);
            // 设置文件类型
            response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=utf-8");
            // 读取文件并输出到浏览器
            File file = FileUtil.file("templates/demo_templates.xlsx");
            outputStream.write(FileUtils.readFileToByteArray(file));
            outputStream.flush();
        } catch (IOException e) {
            log.error("下载文件失败，{}", fileName, e);
        } finally {
            // 不要在此处关闭输出流
            // outputStream.close();
        }
        return Result.success("下载成功");
    }