String ua = request.getHeader("user-agent").toLowerCase();
if (ua.indexOf("micromessenger") > 0 && fileName.equalsIgnoreCase("iReadyInsights.apk")) {
response.setHeader("Access-Control-Allow-Origin", "*");
response.setStatus(HttpStatus.UNAUTHORIZED.value());
response.setContentType("application/json;charset=UTF-8");
response.getWriter().write("请使用浏览器扫描二维码,进行安装包下载");
}