/** Maximum number of documents to cache before indexing */
    protected int maxDocumentCacheSize;

    /** Factory for creating ingesters to process documents */
    private IngestFactory ingestFactory = null;

    /**
     * Initializes the callback implementation after dependency injection.
     * Sets up configuration values and initializes the ingest factory if available.
     */
    @PostConstruct

    /** List of active crawler instances */
    private List<Crawler> crawlerList;

    /** Factory for creating document ingesters */
    private IngestFactory ingestFactory = null;

    /**
     * Default constructor for IndexUpdater.
     * Initializes a new instance with default settings.
     */
    public IndexUpdater() {
        super();
    }

    private static Map<String, Object> componentMap = new HashMap<>();

    private static final String SCRIPT_ENGINE_FACTORY = "scriptEngineFactory";

    private static final String INGEST_FACTORY = "ingestFactory";

    private static final String NOTIFICATION_HELPER = "notificationHelper";

    private static final String SEARCH_HELPER = "searchHelper";