indexUpdater.init();
        assertNotNull(indexUpdater);
    }

    // Test destroy when crawling is not finished
    @Test
    public void test_destroy_notFinished() {
        final List<Crawler> crawlerList = new ArrayList<>();
        final TestCrawler crawler = new TestCrawler();
        crawlerList.add(crawler);
        indexUpdater.setCrawlerList(crawlerList);