fessConfig.getIndexFieldClickCount(), //
                    fessConfig.getIndexFieldFavoriteCount(), //
                    fessConfig.getIndexFieldLang());
            // Initialize Set for O(1) lookup performance
            searchFieldSet = new HashSet<>();
            Collections.addAll(searchFieldSet, searchFields);
        }
        if (facetFields == null) {

        this.dataConfigIds = dataConfigIds;
        return this;
    }

    /**
     * Sets the hot thread monitoring interval for performance analysis.
     * Hot threads help identify performance bottlenecks in the crawler process.
     *
     * @param hotThreadInterval monitoring interval in seconds, -1 to disable
     * @return this CrawlJob instance for method chaining
     */

/**
 * Utility class for handling Base64 encoding and decoding.
 * <p>
 * This class now uses the standard {@link java.util.Base64} implementation
 * instead of a custom implementation, providing better security and performance.
 * The API remains backward compatible with previous versions.
 * </p>
 *
 * @author higa
 */
public abstract class Base64Util {

    /**
     * Do not instantiate.
     */

import jakarta.annotation.PostConstruct;

/**
 * Helper class for managing popular words and suggestions.
 * Provides functionality to retrieve popular words based on search parameters
 * and manages caching for improved performance.
 */
public class PopularWordHelper {
    /** Logger instance for this class */
    private static final Logger logger = LogManager.getLogger(PopularWordHelper.class);

 *
 * <p>Thread-safe operations are supported for registration and retrieval of data stores.
 * The factory caches data store names with a time-based refresh mechanism to improve
 * performance while ensuring up-to-date plugin discovery.</p>
 */
public class DataStoreFactory {
    /** Logger instance for this factory class. */
    private static final Logger logger = LogManager.getLogger(DataStoreFactory.class);

---

## Important Notes

### Thread Safety
- **Suggester**: Thread-safe for queries
- **SuggestIndexer**: Thread-safe for indexing
- **SuggestSettings**: NOT thread-safe for modifications

### Performance
- Use batch operations for indexing (100-500 items)
- Don't call `refresh()` too frequently
- Limit `maxReadingNum` to prevent memory issues
- OpenSearch auto-refreshes every 1 second by default

### Compatibility

    /** HTTP status code for OK */
    private static final int HTTP_STATUS_OK = 200;

    /**
     * Cache for client rules mapping client names to their corresponding URL patterns.
     * This cache improves performance by avoiding repeated parsing of client configuration rules.
     * The key is the rule string, and the value is a pair containing the client name and compiled pattern.
     */

    /**
     * Counter for generating unique session identifiers.
     */
    protected int count = 1;

    /**
     * Cache for storing crawling configurations to improve performance.
     */
    protected Cache<String, CrawlingConfig> crawlingConfigCache;

    /**
     * Initializes the CrawlingConfigHelper by setting up the crawling configuration cache.

        }
        return SortBuilders.fieldSort(field).order(order);
    }

    /**
     * Checks if the specified field is a search field.
     * Uses O(1) Set lookup for improved performance.
     * @param field The field name to check.
     * @return True if the field is a search field, false otherwise.
     */
    protected boolean isSearchField(final String field) {

            return url;
        }
    }

    /**
     * Gets the character encoding for a parent URL from cache or data service.
     * Caches encoding information to improve performance on subsequent requests.
     *
     * @param parentUrl the parent URL to get encoding for
     * @param sessionId the session ID for the crawling session
     * @return the character encoding, or null if not found