paradrop.xlsx 存在 src/main/resource/paradrop.xlsx@RequestMapping(value = "/downloadExcel")    public void downloadExcel(HttpServletResponse response, HttpServletRequest request) throws IOException {        String fileName = "paradrop.xlsx";        InputStream inputStream = Thread.currentThread().getContextClassLoader().getResourceAsStream(fileName);        //强制下载不打开        response.setContentType("application/binary;charset=ISO8859-1");        OutputStream out = response.getOutputStream();        //使用URLEncoder来防止文件名乱码或者读取错误        response.setHeader("Content-Disposition", "attachment; filename="+ URLEncoder.encode(fileName, "UTF-8"));        int b = 0;        byte[] buffer = new byte[1000000];        while (b != -1) {            b = inputStream.read(buffer);            if(b!=-1) out.write(buffer, 0, b);        }        inputStream.close();        out.close();        out.flush();    }