* @return This SuggestIndexer instance.
     */
    public SuggestIndexer setIndexName(final String index) {
        this.index = index;
        return this;
    }

    /**
     * Sets the supported fields.
     * @param supportedFields The supported fields.
     * @return This SuggestIndexer instance.
     */
    public SuggestIndexer setSupportedFields(final String[] supportedFields) {

     */
    public Normalizer getNormalizer() {
        return normalizer;
    }

    /**
     * Creates a default SuggestIndexer instance.
     * @return A SuggestIndexer instance.
     */
    protected SuggestIndexer createDefaultIndexer() {
        return new SuggestIndexer(client, getUpdateAlias(index), readingConverter, contentsReadingConverter, normalizer, analyzer,
                suggestSettings, threadPool);

Main operations: `suggest()`, `popularWords()`, `indexer()`, `createIndexIfNothing()`, `createNextIndex()`, `switchIndex()`, `removeDisableIndices()`

### SuggestIndexer (Indexing Engine)
Location: `src/main/java/org/codelibs/fess/suggest/index/SuggestIndexer.java`

Handles all indexing operations, content parsing, and word management (bad words, elevate words).

### SuggestSettings (Configuration)

    @Test
    public void test_setNullIndexName() throws Exception {
        SuggestIndexer indexer = suggester.indexer();
        // Setting null index name should be allowed (though may cause issues later)
        indexer.setIndexName(null);
    }

    @Test
    public void test_setNullSupportedFields() throws Exception {
        SuggestIndexer indexer = suggester.indexer();
        // Setting null fields should be allowed

/**
 * Internal operations class for core indexing functionality.
 * Handles indexing of SuggestItem objects with bad word filtering.
 *
 * <p>This class is package-private and intended for internal use by SuggestIndexer.
 */
public class IndexingOperations {

    private static final Logger logger = LogManager.getLogger(IndexingOperations.class);

    private final Client client;
    private final SuggestSettings settings;

/**
 * Internal operations class for bad word and elevate word management.
 * Handles adding, deleting, and restoring special words.
 *
 * <p>This class is package-private and intended for internal use by SuggestIndexer.
 */
public class WordManagementOperations {

    private static final Logger logger = LogManager.getLogger(WordManagementOperations.class);

    private final SuggestSettings settings;

/**
 * Internal operations class for deletion functionality.
 * Handles deletion of suggest items by ID, query, or kind.
 *
 * <p>This class is package-private and intended for internal use by SuggestIndexer.
 */
public class DeletionOperations {

    private static final Logger logger = LogManager.getLogger(DeletionOperations.class);

    /** Default page size for scroll operations. */

/**
 * Internal operations class for content-based indexing functionality.
 * Handles indexing from query logs, documents, and search words.
 *
 * <p>This class is package-private and intended for internal use by SuggestIndexer.
 */
public class ContentIndexingOperations {

    private static final Logger logger = LogManager.getLogger(ContentIndexingOperations.class);

    private final Client client;

        assertTrue(remainingWordsCount < totalWordsCount);
        assertTrue(remainingWordsCount > 0);
    }

    @Test
    public void test_setters() throws Exception {
        SuggestIndexer indexer = suggester.indexer();

        assertNotNull(indexer.setIndexName("test-index"));
        assertNotNull(indexer.setSupportedFields(new String[] { "field1", "field2" }));

│   │   ├── suggest/                # Suggestion requests
│   │   └── popularwords/           # Popular words requests
│   ├── index/                      # Indexing functionality
│   │   ├── SuggestIndexer.java     # Main indexing API
│   │   ├── contents/               # Content parsers and readers
│   │   └── writer/                 # Index writing strategies
│   ├── converter/                  # Text conversion utilities