assertNotNull(retrieved);
        assertEquals("test-session", retrieved.getSessionId());
        assertEquals("http://example.com", retrieved.getUrl());
    }

    public void test_urlQueue_setNull() {
        // Set a UrlQueue first
        UrlQueue<?> urlQueue = createMockUrlQueue("test", "http://test.com");
        CrawlingParameterUtil.setUrlQueue(urlQueue);