List<String> initialList = new ArrayList<>();
        initialList.add("item1");
        initialList.add("item2");
        dataMap.put("items", initialList);

        // Add a new value
        transformer.putResultDataBody(dataMap, "items", "item3");

        Object result = dataMap.get("items");
        assertTrue(result instanceof Object[]);
        Object[] resultArray = (Object[]) result;

        SuggestItem item5 = new SuggestItem(new String[] { "テスト" }, readings, new String[] { "content" }, 5, 0, -1, new String[] { "tag1" },
                new String[] { SuggestConstants.DEFAULT_ROLE }, null, SuggestItem.Kind.DOCUMENT);

        SuggestItem[] mergedItems = writer.mergeItems(new SuggestItem[] { item1, item2, item3, item4, item5 });

        assertNotNull(mergedItems);

        StopwordsItem item3 = new StopwordsItem(1, "word");

        // Two items with null input should be equal
        assertTrue(item1.equals(item2));

        // Item with null input should not equal item with non-null input
        assertFalse(item3.equals(item1));
        assertFalse(item1.equals(item3));

        // Symmetry
        assertTrue(item1.equals(item2));

        assertTrue(item1.equals(item2));

        // Item with null input should not equal item with non-null input
        assertFalse(item3.equals(item1));
        assertFalse(item1.equals(item3));

        // Symmetry
        assertTrue(item1.equals(item2));
        assertTrue(item2.equals(item1));
    }

    @Test
    public void test_toString() {
        // Test toString method

        assertFalse(item1.equals(item3));

        // Item with null output should not equal item with different inputs
        CharMappingItem item4 = new CharMappingItem(4L, inputs3, null);
        assertFalse(item1.equals(item4));

        // Symmetry
        assertTrue(item1.equals(item2));
        assertTrue(item2.equals(item1));
    }

    @Test
    public void test_toString() {

        assertEquals(2, result.size());

        CharMappingItem item1 = result.get(0);
        assertArrayEquals(new String[] { "α", "β" }, item1.getInputs());
        assertEquals("γ", item1.getOutput());

        CharMappingItem item2 = result.get(1);
        assertArrayEquals(new String[] { "中", "文" }, item2.getInputs());
        assertEquals("字", item2.getOutput());
    }

    // Test with very long input line

        assertArrayEquals(languages, item.getLanguages());
        assertEquals(1, item.getKinds().length);
        assertEquals(SuggestItem.Kind.QUERY, item.getKinds()[0]);
        assertEquals(50L, item.getQueryFreq());
        assertEquals(100L, item.getDocFreq());
        assertEquals(1.5f, item.getUserBoost(), 0.001f);
        assertNotNull(item.getTimestamp());
        assertNotNull(item.getId());
    }

    @Test

        // Test getting non-existing item
        OptionalEntity<ProtwordsItem> item = protwordsFile.get(999);
        assertFalse(item.isPresent());
    }

    @Test
    public void test_get_withUnloadedData() {
        // Test getting item when data is not loaded yet
        OptionalEntity<ProtwordsItem> item = protwordsFile.get(1);
        assertTrue(item.isPresent());
        assertEquals("test1", item.get().getInput());
    }

    }

    /**
     * Merges two suggest items.
     * @param item1 The first suggest item.
     * @param item2 The second suggest item.
     * @return The merged suggest item.
     */
    public static SuggestItem merge(final SuggestItem item1, final SuggestItem item2) {
        return SuggestItemMerger.merge(item1, item2);
    }

    /**
     * Checks if the suggest item contains any of the given bad words.

        source.put(FieldNames.TIMESTAMP, System.currentTimeMillis());

        SuggestItem item = SuggestItem.parseSource(source);

        assertNotNull(item);
        assertEquals("test", item.getText());
        assertEquals(100L, item.getQueryFreq());
        assertEquals(50L, item.getDocFreq());
        assertEquals(2.0f, item.getUserBoost(), 0.001f);
    }

    @Test