String[] nullValues = defaultContentsParser.getFieldValues(document, "non_existent");
        assertEquals(0, nullValues.length);
    }

    @Test
    public void test_parseSearchWords() throws Exception {
        String[] words = new String[] { "検索", "エンジン" };
        String[][] readings = new String[][] { new String[] { "kensaku" }, new String[] { "enjin" } };