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)

import org.lastaflute.web.validation.Required;

/**
 * Form for uploading stopwords files to the Fess search engine.
 * Stopwords are common words that should be ignored during search indexing and querying.
 * This form is used in the admin interface to upload custom stopwords dictionary files.
 */
public class UploadForm {

    /**

     * and performs bulk indexing operations with proper error handling.
     *
     * @param searchEngineClient the search engine client to use for indexing
     * @param docList the list of documents to be indexed
     * @throws SearchEngineClientException if the bulk indexing operation fails
     */
    public void sendDocuments(final SearchEngineClient searchEngineClient, final DocList docList) {
        if (docList.isEmpty()) {

 *
 * <p>This exception can be thrown with a message, a cause, or both.</p>
 *
 * <pre>
 * Example usage:
 * throw new SuggestIndexException("Indexing error occurred");
 * throw new SuggestIndexException(new IOException("IO error"));
 * throw new SuggestIndexException("Indexing error", new IOException("IO error"));
 * </pre>
 *
 * @see SuggesterException
 */
public class SuggestIndexException extends SuggesterException {

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

 * <li>Transforms document data using appropriate transformers</li>
 * <li>Applies document boosting rules and click/favorite count enhancements</li>
 * <li>Sends processed documents to the search engine for indexing</li>
 * <li>Manages cleanup of processed crawler session data</li>
 * </ul>
 *
 * <p>The updater runs continuously until crawling is finished and all documents are processed.

 * This form extends CreateForm to include fields necessary for updating existing mapping dictionary entries.
 * Mapping dictionaries define field mappings and transformations during the indexing process.
 *
 */
public class EditForm extends CreateForm {

    /**
     * Creates a new EditForm instance.
     */
    public EditForm() {
        super();
    }

    /**

import org.opensearch.index.query.QueryBuilders;
import org.opensearch.search.SearchHit;
import org.opensearch.transport.client.Client;

/**
 * The SuggestIndexer class is responsible for indexing and managing suggest items in an OpenSearch index.
 * It provides methods to index, delete, and manage suggest items, including handling bad words and elevate words.
 *
 * <p>Constructor:
 * <ul>

 */
package org.codelibs.fess.exception;

/**
 * Exception thrown when requested content cannot be found.
 * Typically used when a document or resource is not available during crawling or indexing.
 */
public class ContentNotFoundException extends FessSystemException {

    private static final long serialVersionUID = 1L;

    /**

import jakarta.validation.constraints.Size;

/**
 * Form class for creating new stopwords dictionary entries.
 * This form handles the creation of stopwords that should be
 * excluded from search indexing and analysis.
 *
 */
public class CreateForm {

    /**
     * Creates a new CreateForm instance.
     */
    public CreateForm() {
    }