下载文件之前已准备就绪[关闭]

/*taking blob from database and saved on a folder*/

File f = new File("file name");
for (int i = 0; i < datos.size(); i++) {
    /*write on the file*/
}


response.setContentType("application/octet-stream");
response.setHeader("Content-Disposition", String.format("attachment; filename=\"%s\"", f.getName()));