JR

// Producer-Consumer example in JR
public class ProducerConsumer {
    static op void put(int item);
    static op int get();

    static int[] buffer = new int[10];
    static int head = 0, tail = 0, count = 0;

    process Producer {
        for (int i = 1; i <= 5; i++) {
            System.out.println("Producer producing: " + i);
            send put(i);
        }
    }

    process Consumer {
        for (int i = 1; i <= 5; i++) {
            int item;
            receive get() returns item;
            System.out.println("Consumer consumed: " + item);
        }
    }

    process Manager {
        while (true) {
            int item;
            receive put(item) {
                buffer[tail] = item;
                tail = (tail + 1) % 10;
                count++;
            }
            [] count > 0; receive get() returns item {
                item = buffer[head];
                head = (head + 1) % 10;
                count--;
                return item;
            }
        }
    }
}