}

    /**
     * Test getAnchorSet with list containing only nulls and blanks
     */
    @Test
    public void test_getAnchorSet_withListContainingOnlyNullsAndBlanks() {
        FessCrawlerThread crawlerThread = new FessCrawlerThread();

        List<String> urls = new ArrayList<>();
        urls.add(null);
        urls.add("");
        urls.add("   ");