基于http请求检测Web应用程序中的移动浏览器的标准方法

We are beginning to go down the path of mobile browser support for an enterprise e-commerce webapp (Java/Servlet based). Of course there are many decisions to be made, but it seems to me the cornerstone is to be able to reliably detect mobile browsers, and make decisions on the content to be returned accordingly. Is there a standard way to make this determination (quickly) based on the http request, and ideally glean more information about the given browser and device making the request (screen size, html capabilities, etc?).We are beginning to go down the path of mobile