Sheep.java

package org.example;

import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.Executors;
import java.util.concurrent.locks.LockSupport;

class Task {
    int id;
    String data;
    Thread thread;

    public Task(int id, String data, Thread thread) {
        this.id = id;
        this.data = data;
        this.thread = thread;
    }

    @Override
    public String toString() {
        return "Task{" +
                "id=" + id +
                ", data='" + data + '\'' +
                ", thread=" + thread +
                '}';
    }
}

public class Sheep {
    public static void main(String[] args) {
        var blockingQueue = new ArrayBlockingQueue<Task>(10);
        var pool = Executors.newFixedThreadPool(10);
        pool.execute(() -> {
            while (true) {
                try {
                    Task task = blockingQueue.take();
                    task.data = task.id + " FINISHED.";
                    LockSupport.unpark(task.thread);
                } catch (InterruptedException e) {
                    throw new RuntimeException(e);
                }
            }

        });

        for (int i = 0; i < Integer.MAX_VALUE; i++) {

            int finalI = i;
            pool.execute(() -> {
                var task = new Task(finalI, null, Thread.currentThread());
                try {
                    blockingQueue.put(task);
                } catch (InterruptedException e) {
                    throw new RuntimeException(e);
                }
                LockSupport.park();
                if (task.data == null) {
                    System.out.println(task);
                    System.out.println(task);
                }
                try {
                    Thread.sleep(1);
                } catch (InterruptedException e) {
                    throw new RuntimeException(e);
                }
            });

        }
    }
}