How to get browser information in JSP?

The following jsp will output your ip address and user-agent:

Your user-agent is: <%=request.getHeader("user-agent")%><br/>
Your IP address is: <%=request.getRemoteAddr()%><br/>

To find out what browser and/or OS the user is using, parse the user-agent header.

For example:

<%
String userAgent = request.getHeader("user-agent");
if (userAgent.indexOf("MSIE") > -1) {
  out.println("Your browser is Microsoft Internet Explorer<br/>");
}
%>

For a list of user agents, look here.

要判斷Android 很簡單，Agent 裡會有 Android:

目前熱門行動的裝置的User Agent String:

1. iPad: 有兩個，擇一使用
   (1)

   Mozilla/5.0 (iPad; U; CPU OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.10 (KHTML, like Gecko) Version/4.0.4 Mobile/7B334b Safari/531.21.10

   (2)

   Mozilla/5.0(iPad; U; CPU iPhone OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.10 (KHTML, like Gecko) Version/4.0.4 Mobile/7B314 Safari/531.21.10

    

2. iPod

   Mozilla/5.0 (iPod; U; CPU iPhone OS 3_0 like Mac OS X; en-us) AppleWebKit/528.18 (KHTML, like Gecko) Version/4.0 Mobile/7A341 Safari/528.16

    

3. iPhone

   Mozilla/5.0 (iPhone; U; CPU iPhone OS 3_0 like Mac OS X; en-us) AppleWebKit/528.18 (KHTML, like Gecko) Version/4.0 Mobile/7A341 Safari/528.16

    

4. Android上的瀏覽器
   Android系統的行動裝置幾乎都有“Android”字眼，且多搭配webkit引擎的瀏覽器，所以可用這兩者作為關鍵字

而Apple產品的User Agent String幾乎都包含iPhone字眼。