@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

    CountDownLatch doneSignal = new CountDownLatch(1);

    Thread thread =
        new Thread() {
          @Override
          public void run() {
            try {
              cacheRef.get().getUnchecked(3);
            } finally {
              doneSignal.countDown();
            }
          }
        };
    thread.setUncaughtExceptionHandler(
        new UncaughtExceptionHandler() {

            w.write(payload, payload.length, out);

            // Give the writer thread time to process and set exception
            w.wait(100);
        }

        // Wait a bit more to ensure exception is captured
        Thread.sleep(100);

        // Act + Assert: checkException should throw the SmbException captured by the thread

      }
    }

    void stopInterrupting() {
      shouldStop = true;
    }
  }

  /** Interrupts the current thread after sleeping for the specified delay. */
  static void requestInterruptIn(long time, TimeUnit unit) {
    checkNotNull(unit);
    Thread interruptee = Thread.currentThread();
    new Thread(
            new Runnable() {
              @Override
              public void run() {
                try {

        return instance;
    }

    /**
     * Starts the process.
     */
    public synchronized void start() {
        if (thread == null) {
            thread = new Thread(this, "CoreLib-TimeoutManager");
            thread.setDaemon(true);
            thread.start();
            if (logger.isDebugEnabled()) {
                logger.debug("TimeoutManager started.");
            }
        }
    }

        // Test thread safety with concurrent operations
        final int threadCount = 10;
        Thread[] threads = new Thread[threadCount];
        final boolean[] results = new boolean[threadCount];

        for (int i = 0; i < threadCount; i++) {
            final int index = i;
            threads[i] = new Thread(() -> {
                String thumbnailId = "concurrent-" + index;

  /**
   * Returns an exception handler that exits the system. This is particularly useful for the main
   * thread, which may start up other, non-daemon threads, but fail to fully initialize the
   * application successfully.
   *
   * <p>Example usage:
   *
   * <pre>
   * public static void main(String[] args) {
   *   Thread.currentThread().setUncaughtExceptionHandler(UncaughtExceptionHandlers.systemExit());
   *   ...
   * </pre>
   *

    Stopwatch stopwatch = Stopwatch.createStarted();
    Thread thread = new Thread(new JoinTarget(15));
    thread.start();
    thread.join();
    assertFalse(thread.isAlive());

    joinUninterruptibly(thread);
    joinUninterruptibly(thread, 0, MILLISECONDS);
    joinUninterruptibly(thread, -42, MILLISECONDS);
    joinUninterruptibly(thread, LONG_DELAY_MS, MILLISECONDS);

        // Test thread safety
        final int threadCount = 10;
        final int docsPerThread = 10;
        final List<Thread> threads = new ArrayList<>();
        final AtomicInteger successCount = new AtomicInteger(0);

        for (int i = 0; i < threadCount; i++) {
            final int threadId = i;
            Thread thread = new Thread(() -> {

      return;
    }
    TimedWaiterThread thread = new TimedWaiterThread(new AbstractFuture<Object>() {}, 2, SECONDS);
    thread.start();
    thread.awaitWaiting();
    Thread.class.getMethod("suspend").invoke(thread);
    // Sleep for enough time to add 1500 milliseconds of overwait to the get() call.
    long toWaitMillis = 3500 - NANOSECONDS.toMillis(System.nanoTime() - thread.startTime);
    Thread.sleep(toWaitMillis);