import java.util.LinkedList;
import java.util.Queue;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class MultiProducerConsumer {
    private static final int CAPACITY = 5;
    private final Queue<Integer> queue = new LinkedList<>();
    private final Lock lock = new ReentrantLock();
    private final Condition notEmpty = lock.newCondition();
    private final Condition notFull = lock.newCondition();

    // Producer
    class Producer implements Runnable {
        @Override
        public void run() {
            int value = 0;
            while (true) {
                lock.lock();
                try {
                    while (queue.size() == CAPACITY) {
                        notFull.await();
                    }
                    queue.offer(value);
                    System.out.println(Thread.currentThread().getName() + " produced " + value);
                    value++;
                    notEmpty.signalAll();
                } catch (InterruptedException e) {
                    Thread.currentThread().interrupt();
                } finally {
                    lock.unlock();
                }
            }
        }
    }

    // Consumer
    class Consumer implements Runnable {
        @Override
        public void run() {
            while (true) {
                lock.lock();
                try {
                    while (queue.isEmpty()) {
                        notEmpty.await();
                    }
                    int value = queue.poll();
                    System.out.println(Thread.currentThread().getName() + " consumed " + value);
                    notFull.signalAll();
                } catch (InterruptedException e) {
                    Thread.currentThread().interrupt();
                } finally {
                    lock.unlock();
                }
            }
        }
    }

    public static void main(String[] args) {
        MultiProducerConsumer pc = new MultiProducerConsumer();

        // Starting multiple producers and consumers
        new Thread(pc.new Producer(), "Producer1").start();
        new Thread(pc.new Producer(), "Producer2").start();
        new Thread(pc.new Consumer(), "Consumer1").start();
        new Thread(pc.new Consumer(), "Consumer2").start();
    }
}