*/
    public void addField(final String field) {
        fields.add(field);
    }

    /**
     * Adds a kind to filter by.
     * @param kind The kind.
     */
    public void addKind(final String kind) {
        kinds.add(kind);
    }

    /**
     * Sets whether to return detailed suggestion information.

    }

    /**
     * Merges two Kind arrays, maintaining uniqueness.
     */
    private static SuggestItem.Kind[] mergeKinds(final SuggestItem.Kind[] kinds1, final SuggestItem.Kind[] kinds2) {
        final Set<SuggestItem.Kind> merged = new LinkedHashSet<>();

        if (kinds1 != null) {
            Collections.addAll(merged, kinds1);
        }

        if (kinds2 != null) {

            }
        }
    }

    /**
     * Concatenates kind arrays, avoiding duplicates.
     * @param kinds The initial kind array.
     * @param newKinds The new kind array to add.
     * @return The concatenated kind array.
     */
    protected static Kind[] concatKinds(final Kind[] kinds, final Kind... newKinds) {
        if (kinds == null) {
            return newKinds;
        }

        final SuggestItem.Kind[] itemKinds = new SuggestItem.Kind[kinds.size()];
        for (int i = 0; i < kinds.size(); i++) {
            final String kind = kinds.get(i);
            if (kind.equals(SuggestItem.Kind.DOCUMENT.toString())) {
                itemKinds[i] = SuggestItem.Kind.DOCUMENT;
            } else if (kind.equals(SuggestItem.Kind.QUERY.toString())) {

        return deleteWordsByKind(index, FieldNames.QUERY_FREQ, SuggestItem.Kind.QUERY, item -> item.setQueryFreq(0),
                SuggestItem.Kind.DOCUMENT, SuggestItem.Kind.USER);
    }

    /**
     * Common method to delete words by kind.
     *
     * @param index The index name
     * @param freqField The frequency field name
     * @param kindToRemove The kind to remove
     * @param freqSetter The consumer to set frequency to 0

        source.put(FieldNames.TAGS, Arrays.asList("tag1"));
        source.put(FieldNames.ROLES, Arrays.asList("role1"));
        source.put(FieldNames.LANGUAGES, Arrays.asList("en"));
        source.put(FieldNames.KINDS, Arrays.asList("document"));
        source.put(FieldNames.TIMESTAMP, System.currentTimeMillis());

        SuggestItem item = SuggestItemSerializer.fromSource(source);

        assertNotNull(item);

### SuggestItem (Domain Entity)
Location: `src/main/java/org/codelibs/fess/suggest/entity/SuggestItem.java`

Core attributes: `text`, `timestamp`, `queryFreq`, `docFreq`, `userBoost`, `readings`, `tags`, `roles`, `languages`, `kinds`

Kind types: `DOCUMENT`, `QUERY`, `USER`

---

## Development Workflow

### Build Commands

```bash
mvn compile                              # Compile

	modelType := reflect.ValueOf(dest).Type()
	if modelType.Kind() == reflect.Ptr {
		modelType = modelType.Elem()
	}

	if modelType.Kind() != reflect.Struct {
		if modelType.Kind() == reflect.Interface {
			modelType = reflect.Indirect(reflect.ValueOf(dest)).Elem().Type()
		}

		for modelType.Kind() == reflect.Slice || modelType.Kind() == reflect.Array || modelType.Kind() == reflect.Ptr {
			modelType = modelType.Elem()
		}

                new String[] { SuggestConstants.DEFAULT_ROLE }, null, SuggestItem.Kind.DOCUMENT);

        SuggestItem item2 = new SuggestItem(new String[] { "テスト" }, readings, new String[] { "content" }, 2, 0, -1, new String[] { "tag2" },
                new String[] { SuggestConstants.DEFAULT_ROLE }, null, SuggestItem.Kind.DOCUMENT);

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

                new String[] { SuggestConstants.DEFAULT_ROLE }, null, SuggestItem.Kind.DOCUMENT);
        items[2].setKinds(new SuggestItem.Kind[] { SuggestItem.Kind.DOCUMENT, SuggestItem.Kind.QUERY });

        suggester.indexer().index(items);
        suggester.refresh();

        assertEquals(3, suggester.getAllWordsNum());