重置session時間的filter

package com.mmall.controller.common;

import com.mmall.common.Const;
import com.mmall.pojo.User;
import com.mmall.util.CookieUtil;
import com.mmall.util.JsonUtil;
import com.mmall.util.RedisShardedPoolUtil;
import org.apache.commons.lang.StringUtils;


import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;


/**
 * Created by geely
 */
public class SessionExpireFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {


    }


    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest httpServletRequest = (HttpServletRequest)servletRequest;


        String loginToken = CookieUtil.readLoginToken(httpServletRequest);


        if(StringUtils.isNotEmpty(loginToken)){
            //判斷logintoken是否爲空或者""；
            //如果不爲空的話，符合條件，繼續拿user信息


            String userJsonStr = RedisShardedPoolUtil.get(loginToken);
            User user = JsonUtil.string2Obj(userJsonStr,User.class);
            if(user != null){
                //如果user不爲空，則重置session的時間，即調用expire命令
                RedisShardedPoolUtil.expire(loginToken, Const.RedisCacheExtime.REDIS_SESSION_EXTIME);
            }
        }
        filterChain.doFilter(servletRequest,servletResponse);
    }




    @Override
    public void destroy() {


    }
}