java web 判断请求是手机端还是PC端（代码库）

package config;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class CheckMobile {

    private CheckMobile() {
    }

    // \b 是单词边界(连着的两个(字母字符 与 非字母字符) 之间的逻辑上的间隔),
    // 字符串在编译时会被转码一次,所以是 "\\b"
    // \B 是单词内部逻辑间隔(连着的两个字母字符之间的逻辑上的间隔)
    private static String phoneReg = "\\b(ip(hone|od)|android|opera m(ob|in)i"
            +"|windows (phone|ce)|blackberry"
            +"|s(ymbian|eries60|amsung)|p(laybook|alm|rofile/midp"
            +"|laystation portable)|nokia|fennec|htc[-_]"
            +"|mobile|up.browser|[1-4][0-9]{2}x[1-4][0-9]{2})\\b";
    private static String tableReg = "\\b(ipad|tablet|(Nexus 7)|up.browser"
            +"|[1-4][0-9]{2}x[1-4][0-9]{2})\\b";

    //移动设备正则匹配：手机端、平板
    private static Pattern phonePat = Pattern.compile(phoneReg, Pattern.CASE_INSENSITIVE);
    private static Pattern tablePat = Pattern.compile(tableReg, Pattern.CASE_INSENSITIVE);

    /**
     * 检测是否是移动设备访问
     * @param userAgent 浏览器标识
     * @return true:移动设备接入，false:pc端接入
     */
    public static boolean check(String userAgent){
        if(null == userAgent){
            userAgent = "";
        }
        userAgent = userAgent.toLowerCase();
        // 匹配
        Matcher matcherPhone = phonePat.matcher(userAgent);
        Matcher matcherTable = tablePat.matcher(userAgent);
        return matcherPhone.find() || matcherTable.find();
    }
}

private static boolean isFromMobile(HttpServletRequest request, HttpSession session) {
    //检查是否已经记录访问方式（移动端或pc端）
    boolean isFromMobile = false;
    if (null == session.getAttribute("ua")) {
        //获取ua，用来判断是否为移动端访问
        String userAgent = request.getHeader("USER-AGENT");
        isFromMobile = CheckMobile.check(userAgent);
        //判断是否为移动端访问
        if (isFromMobile) {
            session.setAttribute("ua", "mobile");
        } else {
            session.setAttribute("ua", "pc");
        }
    } else {
        isFromMobile = "mobile".equals(session.getAttribute("ua"));
    }
    return isFromMobile;
}

// 判断手机端还是移动端
String userAgent = servletRequest.getHeader("USER-AGENT");
boolean isMobile = CheckMobile.check(userAgent);
        if (isMobile) {
    model.put("ua", "mobile");
} else {
    model.put("ua", "pc");
}