window.open("/dept/download")

 @RequestMapping(value = "/download", method = RequestMethod.GET)

     public void downstudents(HttpServletRequest request, HttpServletResponse response) throws IOException {

         String filename = request.getSession().getServletContext().getRealPath("/static/email/");

         String filenameZip = filename + "\\dept.xls";

         try {

             response.setContentType("application/x-execl");

             response.setHeader("Content-Disposition",

                     "attachment;filename=" + new String(("dept.xls").getBytes(), "UTF-8"));

             // 读取文件

             InputStream in = new FileInputStream(filenameZip);

             ServletOutputStream outputStream = response.getOutputStream();

             // 写文件

             int b;

             while ((b = in.read()) != -1) {

                 outputStream.write(b);

             }

             in.close();

             outputStream.close();

         } catch (UnsupportedEncodingException e) {

             e.printStackTrace();

         } catch (IOException e) {

             e.printStackTrace();

         }

     }