基于HttpSessionListener实现限制在线用户数量

/**
 * @Author: lizhang10
 * @Date: 2019/6/26 09:49
 * @Description:创建session的时候userCounts加1存入redis，session销毁的时候减1存进redis
 */

public class MyHttpSessionListener implements HttpSessionListener {
    //当前用户数
    private int userCounts=0;
    @Override
    public void sessionCreated(HttpSessionEvent se) {
        //创建session  用户数+1
        userCounts++;
        //保存在线有用户数到redis
        RedisTemplate redisTemplate = null;
        redisTemplate = SpringUtil.getBean("redisTemplate" , RedisTemplate.class);
        redisTemplate.opsForValue().set("userCounts",String.valueOf(userCounts));
    }
    @Override
    public void sessionDestroyed(HttpSessionEvent se) {
        //session销毁  用户数-1
        userCounts--;
        //保存在线有用户数到redis
        RedisTemplate redisTemplate = null;
        redisTemplate = SpringUtil.getBean("redisTemplate" , RedisTemplate.class);
        redisTemplate.opsForValue().set("userCounts",String.valueOf(userCounts));
    }

//查询redis userCounts数量大于5000就提示现在高峰期过一会登陆
 String userCount = redisTemplate.opsForValue().get("userCounts").toString();
                    if (Integer.parseInt(userCount) > 5000) {
                        attr.addFlashAttribute("msg", SysCode.LoginMsg.USER_COUNT);}else{
......
}

标签：在线,redis,RedisTemplate,session,用户数,HttpSessionListener,userCounts,用户数量,redisTemp
来源： https://www.cnblogs.com/AnonymouL/p/11090265.html