Kotlin Simple Rate Limiter

RateLimiter.kt

class RateLimiter(private val period: Long, private val rate: Int) {
    private val times = LinkedList<Long>()

    fun check(): Boolean {
        synchronized(times) {
            val currentTime = System.currentTimeMillis()
            times.removeIf { it < currentTime - period }

            val isLimited = times.size >= rate
            if (!isLimited) {
                times.add(currentTime)
            }

            return isLimited
        }
    }
}