Naive Leaky Bucket Algorithm Implementation

scratch.java

import java.util.LinkedList;
import java.util.stream.Stream;

class Scratch {
    public static void main(String[] args) throws InterruptedException {
        int rate = Integer.parseInt(args[0]);
        int maxBucketSize = Integer.parseInt(args[1]);
        LinkedList<Integer> requestStream = new LinkedList<>(Stream.of(args[2].split(","))
            .map(Integer::parseInt)
            .toList());
        LeakyBucketRateLimiter rateLimiter = new LeakyBucketRateLimiter(rate, maxBucketSize);
        int numRequests = 0;
        int numRequestsRateLimited = 0;
        int numRequestProcessed = 0;

        do {
            System.out.println(rateLimiter);

            if (requestStream.peek() != null) {
                int requests = requestStream.pop();
                numRequests += requests;
                for (int i = 0; i < requests; i++) {
                    if (rateLimiter.putRequest()) {
                        System.out.println("Requests sent");
                    } else {
                        System.out.println("Request rate limited");
                        numRequestsRateLimited++;
                    }
                }
            }
            numRequestProcessed += rateLimiter.getRequest();
            // pretend some work is done
            Thread.sleep(500);
        } while (rateLimiter.hasRequests() || !requestStream.isEmpty());
        System.out.printf("\nSummary\nTotal requests: %s, Rate Limited: %s, Processed: %s%n",
            numRequests, numRequestsRateLimited, numRequestProcessed);
    }

    public static class LeakyBucketRateLimiter {

        final int rate;
        final int maxBucketSize;
        int currentBucketSize;

        public LeakyBucketRateLimiter(int rate, int maxBucketSize) {
            this.rate = rate;
            this.maxBucketSize = maxBucketSize;
            this.currentBucketSize = 0;
        }

        public int getRequest() {
            int val = 0;

            if (currentBucketSize > 0) {
                val = Math.min(rate, currentBucketSize);
                currentBucketSize -= val;
            }
            return val;
        }

        public boolean putRequest() {
            if (currentBucketSize == maxBucketSize) {
                return false;
            }
            currentBucketSize++;
            return true;
        }

        public boolean hasRequests() {
            return currentBucketSize > 0;
        }

        @Override
        public String toString() {
            return "LeakyBucketRateLimiter{" +
                "rate=" + rate +
                ", currentBucketSize=" + currentBucketSize +
                ", maxBucketSize=" + maxBucketSize +
                '}';
        }
    }
}