将数据响应到前端去

            //定义响应流
            String fileName = "文件名_" + System.currentTimeMillis() + ".xls";
            //设置相应流格式信息等
            fileName = new String(fileName.getBytes(), "ISO8859-1");
            response.setContentType("application/octet-stream;charset=ISO8859-1");
            response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
            response.addHeader("Pargam", "no-cache");
            response.addHeader("Cache-Control", "no-cache");
            OutputStream os = response.getOutputStream();



            //将excel对象写到相应流中
            workBook.write(os);
            os.flush();
            os.close();