通过请求头判断是什么浏览器

public String mobile(HttpServletRequest request, HttpServletResponse response) {  
String userAgent = request.getHeader("User-Agent");  
if(userAgent != null) {  
if(userAgent.toLowerCase().indexOf("iphone") > -1) {  
return "苹果手机";  
} else if(userAgent.toLowerCase().indexOf("micromessenger") > -1) {  
return "微信";  
} else if(userAgent.toLowerCase().indexOf("android") > -1) {  
return "android手机";  
}  
}  
return "";  
}