मेमोरी-आधारित दर-सीमाकर्ता का डिज़ाइन

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicInteger;

public class InMemoryRateLimiter {
    private final int limit; // Max requests allowed
    private final long windowMillis; // Time window in milliseconds

    private final ConcurrentHashMap<String, AtomicInteger> counts = new ConcurrentHashMap<>();
    private final ConcurrentHashMap<String, Long> windowStarts = new ConcurrentHashMap<>();

    public InMemoryRateLimiter(int limit, long windowMillis) {
        this.limit = limit;
        this.windowMillis = windowMillis;
    }

    // The allowRequest method will go here
}

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicInteger;

public class InMemoryRateLimiter {
    private final int limit;
    private final long windowMillis;

    private final ConcurrentHashMap<String, AtomicInteger> counts = new ConcurrentHashMap<>();
    private final ConcurrentHashMap<String, Long> windowStarts = new ConcurrentHashMap<>();

    public InMemoryRateLimiter(int limit, long windowMillis) {
        this.limit = limit;
        this.windowMillis = windowMillis;
    }

    public boolean allowRequest(String clientId) {
        long currentTime = System.currentTimeMillis();

        // Get or initialize window start time for this client
        long currentWindowStart = windowStarts.computeIfAbsent(clientId, k -> currentTime);

        // ... more logic to come ...
        return false; // Placeholder
    }
}

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicInteger;

public class InMemoryRateLimiter {
    private final int limit;
    private final long windowMillis;

    private final ConcurrentHashMap<String, AtomicInteger> counts = new ConcurrentHashMap<>();
    private final ConcurrentHashMap<String, Long> windowStarts = new ConcurrentHashMap<>();

    public InMemoryRateLimiter(int limit, long windowMillis) {
        this.limit = limit;
        this.windowMillis = windowMillis;
    }

    public boolean allowRequest(String clientId) {
        long currentTime = System.currentTimeMillis();
        long currentWindowStart = windowStarts.computeIfAbsent(clientId, k -> currentTime);

        // If the current window has expired, reset it
        if (currentTime - currentWindowStart >= windowMillis) {
            windowStarts.put(clientId, currentTime); // Start a new window
            counts.put(clientId, new AtomicInteger(0)); // Reset count
        }

        // ... more logic to come ...
        return false; // Placeholder
    }
}

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicInteger;

public class InMemoryRateLimiter {
    private final int limit;
    private final long windowMillis;

    private final ConcurrentHashMap<String, AtomicInteger> counts = new ConcurrentHashMap<>();
    private final ConcurrentHashMap<String, Long> windowStarts = new ConcurrentHashMap<>();

    public InMemoryRateLimiter(int limit, long windowMillis) {
        this.limit = limit;
        this.windowMillis = windowMillis;
    }

    public boolean allowRequest(String clientId) {
        long currentTime = System.currentTimeMillis();
        long currentWindowStart = windowStarts.computeIfAbsent(clientId, k -> currentTime);

        if (currentTime - currentWindowStart >= windowMillis) {
            windowStarts.put(clientId, currentTime);
            counts.put(clientId, new AtomicInteger(0));
        }

        // Increment count and check if within limit
        AtomicInteger clientCount = counts.computeIfAbsent(clientId, k -> new AtomicInteger(0));
        if (clientCount.incrementAndGet() <= limit) {
            return true; // Request allowed
        } else {
            return false; // Request denied
        }
    }

    public static void main(String[] args) {
        // Example usage will go here
    }
}

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicInteger;

public class InMemoryRateLimiter {
    private final int limit;
    private final long windowMillis;

    private final ConcurrentHashMap<String, AtomicInteger> counts = new ConcurrentHashMap<>();
    private final ConcurrentHashMap<String, Long> windowStarts = new ConcurrentHashMap<>();

    public InMemoryRateLimiter(int limit, long windowMillis) {
        this.limit = limit;
        this.windowMillis = windowMillis;
    }

    public boolean allowRequest(String clientId) {
        long currentTime = System.currentTimeMillis();
        long currentWindowStart = windowStarts.computeIfAbsent(clientId, k -> currentTime);

        if (currentTime - currentWindowStart >= windowMillis) {
            windowStarts.put(clientId, currentTime);
            counts.put(clientId, new AtomicInteger(0));
        }

        AtomicInteger clientCount = counts.computeIfAbsent(clientId, k -> new AtomicInteger(0));
        if (clientCount.incrementAndGet() <= limit) {
            return true;
        } else {
            return false;
        }
    }

    public static void main(String[] args) throws InterruptedException {
        // Allow 3 requests per 5 seconds for "user1"
        InMemoryRateLimiter limiter = new InMemoryRateLimiter(3, 5000);

        String user = "user1";
        System.out.println("Testing rate limiter for " + user + ": 3 requests / 5 seconds\n");

        for (int i = 0; i < 5; i++) {
            boolean allowed = limiter.allowRequest(user);
            System.out.println("Request " + (i + 1) + ": " + (allowed ? "Allowed" : "Denied"));
            if (i == 2) { // After 3rd request, wait for window to reset
                System.out.println("\n--- Max requests reached. Waiting for window reset (5.5s) ---\n");
                Thread.sleep(5500); // Wait for window to reset
            }
        }

        System.out.println("\n--- Testing after window reset ---\n");
        for (int i = 0; i < 2; i++) {
            boolean allowed = limiter.allowRequest(user);
            System.out.println("Request " + (i + 1) + ": " + (allowed ? "Allowed" : "Denied"));
        }
    }
}