* Controls the level of detail in system log messages.
     */
    @Size(max = 10)
    public String logLevel;

    /**
     * Storage service endpoint URL for cloud storage integration.
     * Used for storing files in cloud storage services like S3.
     */
    @Size(max = 1000)
    public String storageEndpoint;

    /**
     * Access key for cloud storage authentication.

        logger.info("Creating new suggest index.");
        suggestHelper.suggester().createNextIndex();

        logger.info("Storing all bad words.");
        suggestHelper.storeAllBadWords(true);

        logger.info("Storing all elevate words.");
        suggestHelper.storeAllElevateWords(true);

        final AtomicInteger exitCode = new AtomicInteger(0);

 */
public class RelatedQueryHelper extends AbstractConfigHelper {
    private static final Logger logger = LogManager.getLogger(RelatedQueryHelper.class);

    /**
     * Map storing related queries organized by virtual host key and search term.
     * The outer map key is the virtual host key, the inner map key is the search term
     * (in lowercase), and the value is an array of related query strings.
     */

 */
public class HostIntervalController extends DefaultIntervalController {

    /** Default cache expire duration in hours */
    private static final long DEFAULT_CACHE_EXPIRE_HOURS = 1L;

    /** Cache storing the last access time for each host. */
    private final Cache<String, AtomicLong> lastTimes;

    /**
     * Constructs a new HostIntervalController with default parameters.
     */
    public HostIntervalController() {

    protected List<String> contentFieldList;

    /** The popular word helper for handling popular words. */
    protected PopularWordHelper popularWordHelper = null;

    /** The interval for storing search logs. */
    protected long searchStoreInterval = 1; // min

    /**
     * Initializes the SuggestHelper.
     * This method sets up the suggester, configures field names, and initializes

    protected int userInfoCacheSize = 10000;

    /** Queue for storing search logs. */
    protected Queue<SearchLog> searchLogQueue = new ConcurrentLinkedQueue<>();

    /** Queue for storing click logs. */
    protected Queue<ClickLog> clickLogQueue = new ConcurrentLinkedQueue<>();

    /** Cache for storing user information. */
    protected LoadingCache<String, UserInfo> userInfoCache;

### Essential Files

| File | Purpose |
|------|---------|
| `Suggester.java` | Main entry point, index management |
| `SuggestIndexer.java` | Indexing operations |
| `SuggestRequest.java` | Query building, scoring |
| `SuggestSettings.java` | Configuration |
| `SuggestItem.java` | Domain model |
| `DefaultContentsParser.java` | Text processing pipeline |

### Key Constants

```java
// Field names (FieldNames.java)

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

    /** Character used to separate cache key components */
    protected static final char CACHE_KEY_SPLITTER = '\n';

    /** Cache for storing popular word lists */
    protected Cache<String, List<String>> cache;

    /** Fess configuration instance */
    protected FessConfig fessConfig;

    /**
     * Default constructor.
     */

    protected int maxErrorCount = 2;

    /** List of finished crawler session IDs for cleanup */
    protected List<String> finishedSessionIdList = new ArrayList<>();

    /** List of document boost matchers for scoring enhancement */
    private final List<DocBoostMatcher> docBoostMatcherList = new ArrayList<>();

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

 * and field configuration handling during the document transformation process.
 */
public interface FessTransformer {

    /**
     * Synchronized LRU cache for storing parent URL encodings.
     * Maps session+parent URL keys to their corresponding character encodings.
     */
    Map<String, String> parentEncodingMap = Collections.synchronizedMap(new LruHashMap<>(1000));

    /**