利用redis做限流器

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package com.inspur.inspurTest.test.redis;

import redis.clients.jedis.Jedis;

/**
 * author yulinshan
 * time 2019/5/23
 * 限流器，利用redis的incr函数做计数，expire做计时失效
 **/
public class Increase {
    static String key = "count";
    static int limitCount = 30;
    public static void main(String[] args) throws InterruptedException {
        Jedis j =new Jedis("127.0.0.1",6379);
        for(int i = 0 ;i < 100 ;i ++ ) {
            if (!checkKey(j)){
                System.out.println("超过限流阈值");
                return;
            }
            incrKey(j);
        }
    }
    private static void incrKey(Jedis j){
        if (j.ttl(key) < 0 ){
            j.incr(key);
            j.expire(key,60);
        }else{
            j.incr(key);
        }
        System.out.println("总计访问次数为："+j.get(key));
    }

    private static boolean checkKey(Jedis j) {
        if (null != j.get(key)) {
            if (Integer.parseInt(j.get(key)) >= limitCount) {
                return false;
            }
        }
        return true;
    }
}

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compile group: 'redis.clients', name: 'jedis', version: '2.9.0'