java 判断浏览器

    String agent = request.getHeader("User-Agent").toLowerCase();
    Pattern pattern = Pattern.compile("msie (\d+)");
    Matcher matcher = pattern.matcher(agent);
    if(matcher.find()){
        int version = Integer.parseInt(matcher.group(1));
        if(version < 9){
            //IE9以下版本
        }
    }

以上一判断lt IE9为例