@Override
    public boolean offer(E o) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.offer(o);
    }

    @Override
    public @Nullable E poll() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.poll();
    }

    @Override
    public E remove() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.remove();
    }

    @Override

     * exception. But there's another race: If the first thread fails with an exception and a second
     * thread immediately fails with the same exception:
     *
     * Thread1: calls setException(), which returns true, context switch before it can CAS
     * seenExceptionsField to its exception
     *
     * Thread2: calls setException(), which returns false, CASes seenExceptionsField to its

 * deterministic.
 *
 * This class ensures that at most one thread is running at a time. This is initially the JUnit test
 * thread, which yields its execution privilege while calling [runTasks], [runNextTask], or
 * [advanceUntil]. These functions don't return until the task threads are all idle.
 *
 * Task threads release their execution privilege in these ways:
 *

        }
      }
    } finally {
      if (interrupted) {
        Thread.currentThread().interrupt();
      }
    }
  }

  /** Invokes {@code toJoin.}{@link Thread#join() join()} uninterruptibly. */
  @J2ktIncompatible
  @GwtIncompatible // concurrency
  public static void joinUninterruptibly(Thread toJoin) {
    boolean interrupted = false;
    try {
      while (true) {
        try {

     *       observing a null thread does not mean the object is safe to reuse.
     *   <li>If this field's value is some other thread object, we know that it's not our thread.
     *   <li>If this field's value == null because it originally belonged to another thread and that
     *       thread cleared it, we still know that it's not associated with our thread

        urlFilter.init(sessionId);

        // Create multiple threads adding patterns
        Thread thread1 = new Thread(() -> {
            for (int i = 0; i < 100; i++) {
                urlFilter.addInclude("https://site" + i + ".com/.*");
            }
        });

        Thread thread2 = new Thread(() -> {
            for (int i = 0; i < 100; i++) {

                }
              });
      thread.start();
      // we want to wait until each thread is WAITING - one thread waiting inside CacheLoader.load
      // (in startSignal.await()), and the others waiting for that thread's result.
      while (thread.isAlive() && thread.getState() != Thread.State.WAITING) {
        Thread.yield();
      }
    }
    gettersStartedSignal.countDown();

    @Override
    public String toString() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.toString();
    }

    @Override
    public boolean equals(@Nullable Object o) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.equals(o);
    }

    @Override
    public int hashCode() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.hashCode();
    }

public class DeferredTest {
    @Test
    public void test_doneBeforeResolve() throws Exception {
        final Deferred<SuggestResponse> deferred = new Deferred<>();

        Thread th = new Thread(() -> {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException ignore) {}
            deferred.resolve(new SuggestResponse("", 0, Collections.emptyList(), 0, null));
        });
        th.start();

          @Override
          void afterRanInterruptiblyFailure(Throwable error) {}
        };
    Thread runner = new Thread(task, "runner");
    runner.start();
    isInterruptibleRegistered.await();
    // trigger the interrupt on another thread since it will block
    Thread interrupter =
        new Thread("Interrupter") {
          @Override
          public void run() {
            task.interruptTask();