// Execute
        UrlQueueImpl<Long> result = service.poll(sessionId);

        // Verify
        assertNull(result);
    }

    public void test_offerAllNewUrls() {
        // Setup
        String sessionId = "session123";
        Queue<UrlQueueImpl<Long>> existingQueue = new LinkedList<>();
        Map<String, AccessResultImpl<Long>> accessResultMap = new HashMap<>();