Repro for IllegalMonitorStateException in ArrayBlockingQueue

Repro.java

import java.util.*;
import java.util.concurrent.*;
import java.util.stream.*;
import java.util.concurrent.atomic.*;

public class Repro {
  public static void main(String[] args) throws Exception {
      ArrayBlockingQueue<Object> q = new ArrayBlockingQueue<>(1);
      ForkJoinPool fj =
        new ForkJoinPool(
            2,
            ForkJoinPool.defaultForkJoinWorkerThreadFactory,
            null,
            true,
            0,
            5,
            1,
            null,
            60_000L,
            TimeUnit.MILLISECONDS);

      AtomicBoolean stop = new AtomicBoolean();

      for (int i = 0; i < 100; i++) {
        int j = i;
        fj.submit(
            () -> {
              try {
                q.put(j);
              } catch (IllegalMonitorStateException e) {
                // SHOULD NEVER HAPPEN? But it will.
                if (!stop.getAndSet(true)) {
                  e.printStackTrace();
        
                  System.out.println("fj state: " + fj);          
                  System.exit(0);
                }
              } catch (InterruptedException e) {
              }
            });
      }

      for (int i = 0; i < 100; i++) {
        System.out.println(": " + q.take() + " " + fj);
      }
  } 
}