mergedItem.setUserBoost(item2.getUserBoost());
        mergedItem.setEmptySource(item2.toEmptyMap());

        // Sum frequencies
        mergedItem.setQueryFreq(item1.getQueryFreq() + item2.getQueryFreq());
        mergedItem.setDocFreq(item1.getDocFreq() + item2.getDocFreq());

        return mergedItem;
    }

    /**
     * Merges readings at a specific index from two reading arrays.
     */

     */
    public Kind[] getKinds() {
        return kinds;
    }

    /**
     * Returns the query frequency of the suggest item.
     * @return The query frequency.
     */
    public long getQueryFreq() {
        return queryFreq;
    }

    /**
     * Returns the document frequency of the suggest item.
     * @return The document frequency.
     */
    public long getDocFreq() {

        map.put(FieldNames.QUERY_FREQ, item.getQueryFreq());
        map.put(FieldNames.DOC_FREQ, item.getDocFreq());
        map.put(FieldNames.USER_BOOST, item.getUserBoost());
        map.put(FieldNames.SCORE, (item.getQueryFreq() + item.getDocFreq()) * item.getUserBoost());
        map.put(FieldNames.TIMESTAMP, item.getTimestamp().toInstant().toEpochMilli());

        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

        SuggestItem item = new SuggestItem(text, readings, null, 0L, 0L, 1.0f, null, null, null, SuggestItem.Kind.QUERY);

        assertEquals(0L, item.getDocFreq());
        assertEquals(0L, item.getQueryFreq());
    }

    @Test
    public void test_maxFrequencies() {
        String[] text = { "test" };
        String[][] readings = { { "test" } };

        SuggestItem item =

        SuggestItem item = items.get(0);
        assertEquals("検索エンジン", item.getText());
        assertEquals(SuggestItem.Kind.QUERY, item.getKinds()[0]);
        assertEquals(1, item.getQueryFreq());
    }

    @Test
    public void test_parseQueryLog2Word() throws Exception {
        QueryLog queryLog = new QueryLog("content:検索エンジン AND content:柿", null);

        assertNotNull(item);
        assertEquals("test text", item.getText());
        assertEquals(10L, item.getDocFreq());
        assertEquals(5L, item.getQueryFreq());
        assertEquals(1.5f, item.getUserBoost(), 0.001f);
    }

    @Test
    public void testToJson() {
        String[] text = { "json test" };
        String[][] readings = { { "reading" } };

        SuggestItem merged = SuggestItemMerger.merge(item1, item2);

        assertNotNull(merged);
        assertEquals(30L, merged.getDocFreq()); // 10 + 20
        assertEquals(20L, merged.getQueryFreq()); // 5 + 15
        assertEquals(2.0f, merged.getUserBoost(), 0.001f); // max(1.0, 2.0)
    }

    @Test
    public void testMerge_tags() {
        SuggestItem item1 = createItemWithTags("text", "tag1", "tag2");

        }

        secondLine.put("fields", item.getFields());
        secondLine.put("queryFreq", item.getQueryFreq());
        secondLine.put("docFreq", item.getDocFreq());
        secondLine.put("userBoost", item.getUserBoost());
        secondLine.put("score", (item.getQueryFreq() + item.getDocFreq()) * item.getUserBoost());
        secondLine.put("tags", item.getTags());

        assertEquals(word, suggestItem.getText());
        assertEquals(boost, suggestItem.getUserBoost(), 0.001f);
        // The queryFreq and docFreq might be handled differently by SuggestItem
        assertTrue(suggestItem.getQueryFreq() >= 0);
        assertTrue(suggestItem.getDocFreq() >= 0);

        // Check readings
        String[][] itemReadings = suggestItem.getReadings();
        assertNotNull(itemReadings);