try {
            assertFalse(suggestHelper.deleteAllWords());
        } catch (Exception e) {
            assertTrue(true);
        }
    }

    public void test_deleteDocumentWords() {
        try {
            assertFalse(suggestHelper.deleteDocumentWords());
        } catch (Exception e) {
            assertTrue(true);
        }
    }

        assertEquals(0, suggester.getAllWordsNum());
        assertEquals(0, suggester.getDocumentWordsNum());
        assertEquals(0, suggester.getQueryWordsNum());
    }

    @Test
    public void test_deleteDocumentWords() throws Exception {
        SuggestItem[] items = getItemSet1();
        suggester.indexer().index(items);
        suggester.refresh();

        assertEquals(2, suggester.getAllWordsNum());