* <li>{@link #deleteElevateWord(String, boolean)} - Delete an elevate word and optionally apply it.
 * <li>{@link #restoreElevateWord()} - Restore elevate words.
 * <li>{@link #deleteOldWords(ZonedDateTime)} - Delete old words based on a threshold date.
 * <li>{@link #setIndexName(String)} - Set the index name.
 * <li>{@link #setSupportedFields(String[])} - Set the supported fields.

        suggester.refresh();

        long totalWordsCount = suggester.getAllWordsNum();
        assertTrue(totalWordsCount > oldWordsCount);

        SuggestDeleteResponse deleteResponse = suggester.indexer().deleteOldWords(threshold);

        assertNotNull(deleteResponse);
        assertFalse(deleteResponse.hasError());

        suggester.refresh();
        long remainingWordsCount = suggester.getAllWordsNum();

        SuggestResponse response3 = suggester.suggest().setQuery("検索").setSuggestDetail(true).execute().getResponse();
        assertEquals(1, response3.getNum());

        suggester.indexer().deleteOldWords(threshold);
        suggester.refresh();

        SuggestResponse response4 = suggester.suggest().setQuery("柿").setSuggestDetail(true).execute().getResponse();
        assertEquals(0, response4.getNum());