String key = "rate_limit:" + userId;
// 模擬用戶(hù)請(qǐng)求訪問(wèn)
List<String> tokens = redis.lrange(key, 0, -1);

int maxTokens = 50;
long timeInterval = 1 * 1000;
long now = System.currentTimeMillis();

long expiredTokens = tokens.stream().filter(t -> Long.parseLong(t) < now - timeInterval).count();
tokens = tokens.subList((int) expiredTokens, tokens.size());
long remainTokens = maxTokens - tokens.size();

if (remainTokens < 1) {
    throw new RateLimitException("請(qǐng)求太頻繁，請(qǐng)稍后再試！");
}

Long expiresIn = now + timeInterval;
redis.multi();
redis.rpush(key, String.valueOf(expiresIn));
redis.pexpire(key, timeInterval);
redis.exec();

public boolean isAllowed(String key, int limit, int timeout) {
    Jedis jedis = getJedis();
    long count = jedis.incr(key);
    if (count == 1) {
        jedis.expire(key, timeout);
    }
    boolean allowed = count <= limit;
    if (!allowed) {
        jedis.del(key);
    }
    jedis.close();
    return allowed;
}

public boolean isAllowed(String key, int capacity, double leakRate, int reqCount) {
    Jedis jedis = getJedis();
    long nowTime = System.currentTimeMillis();
    String luaScript =
          "local currentCapacity = tonumber(redis.call('hget', KEYS[1], 'leftCapacity'))\n"
        + "if currentCapacity == nil then\n"
        + "    redis.call('hset', KEYS[1], 'lastTime', ARGV[2])\n"
        + "    redis.call('hset', KEYS[1], 'leftCapacity', ARGV[1] - 1)\n"
        + "    return 1\n"
        + "end\n"
        + "local changeTime = tonumber(redis.call('hget', KEYS[1], 'lastTime'))\n"
        + "local delayMillSeconds = nowTime - changeTime\n"
        + "local currentDelayCount = tonumber(delayMillSeconds*ARGV[3])\n"
        + "local currentCapacity = math.min(currentDelayCount+currentCapacity, ARGV[1])\n"
        + "if currentCapacity >= ARGV[4] then\n"
        + "    return 0\n"
        + "else\n"
        + "    redis.call('hset', KEYS[1], 'leftCapacity', currentCapacity-1)\n"
        + "    redis.call('hset', KEYS[1], 'lastTime', nowTime)\n"
        + "    return 1\n"
        + "end";
    Object result = jedis.eval(
        luaScript,
        Collections.singletonList(key),
        Arrays.asList(String.valueOf(capacity), String.valueOf(nowTime), String.valueOf(leakRate), String.valueOf(reqCount))
    );
    boolean allowed = (result instanceof Long ? (Long) result : 0L) == 1L;
    jedis.close();
    return allowed;
}

public boolean isAllowed(String key, int capacity, double rate, int reqCount) {
    long nowTime = System.currentTimeMillis();
    Jedis jedis = getJedis();
    String luaScript =
          "local currentLimit = tonumber(redis.call('get', KEYS[1]) or '0')\n"
        + "if currentLimit + ARGV[1] > tonumber(KEYS[2]) then\n"
        + "    return false\n"
        + "else\n"
        + "    redis.call('incrby', KEYS[1], ARGV[1])\n"
        + "    redis.call('expire', KEYS[1], ARGV[2])\n"
        + "    return true\n"
        + "end";
    Object result = jedis.eval(luaScript, 2, key, String.valueOf(capacity), String.valueOf(reqCount), String.valueOf(rate * (nowTime / 1000)));
    boolean allowed = (result instanceof Boolean ? (Boolean) result : false);
    jedis.close();
    return allowed;
}

public boolean isAllowed(String ip, int limit, int interval) {
    Jedis jedis = getJedis();
    String key = "ip:" + ip;
    long count = jedis.incr(key);
    if (count == 1) {
        jedis.expire(key, interval);
    }
    boolean allowed = count <= limit;
    if (!allowed) {
        jedis.del(key);
    }
    jedis.close();
    return allowed;
}

public boolean isAllowed(String ip, int limit, int interval) {
    JedisCluster jedis = getJedisCluster();
    String key = "ip:" + ip;
    long count = jedis.incr(key);
    if (count == 1) {
        jedis.expire(key, interval);
    }
    boolean allowed = count <= limit;
    if (!allowed) {
        jedis.del(key);
    }
    return allowed;
}

/**
 * 獲取緩存值方法
 * @param key 緩存鍵值
 * @return 緩存值
 */
public String getCacheValue(String key) {
    String value = cache.get(key);
    if (value == null) { //緩存未命中
        //使用互斥鎖
        Lock lock = redisson.getLock(key);
        if (lock.tryLock()) { //嘗試獲取鎖
            try {
                value = cache.get(key); //再次嘗試獲取緩存
                if (value == null) { //如果仍然未命中，從數(shù)據(jù)庫(kù)中獲取
                    value = db.get(key);
                    cache.put(key, value); //將查詢(xún)結(jié)果放入緩存
                }
            } finally {
                lock.unlock(); //釋放鎖
            }
        } else {
            Thread.sleep(100); //自旋一段時(shí)間后重試
            return getCacheValue(key);
        }
    }
    return value;
}

/**
 * 獲取緩存值方法
 * @param key 緩存鍵值
 * @return 緩存值
 */
public String getCacheValue(String key) {
    String value = cache.get(key);
    if (value == null) { //緩存未命中
        //使用分布式鎖
        RLock lock = redisson.getFairLock(key);
        if (lock.tryLock()) { //嘗試獲取鎖
            try {
                value = cache.get(key); //再次嘗試獲取緩存
                if (value == null) { //如果仍然未命中，從數(shù)據(jù)庫(kù)中獲取
                    value = db.get(key);
                    cache.put(key, value); //將查詢(xún)結(jié)果放入緩存
                }
            } finally {
                lock.unlock(); //釋放鎖
            }
        } else {
            Thread.sleep(100); //自旋一段時(shí)間后重試
            return getCacheValue(key);
        }
    }
    return value;
}