public void test_urlFilter() {
        assertNull(crawlerContext.getUrlFilter());

        TestUrlFilter filter = new TestUrlFilter();
        crawlerContext.setUrlFilter(filter);
        assertSame(filter, crawlerContext.getUrlFilter());

        crawlerContext.setUrlFilter(null);
        assertNull(crawlerContext.getUrlFilter());
    }

    /**
     * Test ruleManager getter and setter
     */

        try {
            final CrawlerContext crawlerContext = new CrawlerContext();
            final String sessionId = "id1";
            urlFilter.init(sessionId);
            crawlerContext.setUrlFilter(urlFilter);
            CrawlingParameterUtil.setCrawlerContext(crawlerContext);
            httpClient.init();
            httpClient.processRobotsTxt(url);