/**
 * API action for admin file configuration management.
 * Provides RESTful API endpoints for managing file crawling configuration settings in the Fess search engine.
 * File configurations define settings for crawling file systems, FTP servers, and other file-based data sources.
 *
 */
public class ApiAdminFileconfigAction extends FessApiAdminAction {

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

 * It manages the crawling lifecycle, including initialization, execution coordination,
 * monitoring, and cleanup operations.
 *
 * <p>The crawler can operate in different modes based on command-line options:
 * <ul>
 * <li>Web crawling - crawls web sites and web content</li>
 * <li>File system crawling - crawls file systems and documents</li>

  // Timed Get
  // There are a few design constraints to consider
  // * We want to be responsive to small timeouts, unpark() has non trivial latency overheads (I
  //   have observed 12 micros on 64-bit linux systems to wake up a parked thread). So if the
  //   timeout is small we shouldn't park(). This needs to be traded off with the cpu overhead of
  //   spinning, so we use SPIN_THRESHOLD_NANOS which is what AbstractQueuedSynchronizer uses for

  // Timed Get
  // There are a few design constraints to consider
  // * We want to be responsive to small timeouts, unpark() has non trivial latency overheads (I
  //   have observed 12 micros on 64-bit linux systems to wake up a parked thread). So if the
  //   timeout is small we shouldn't park(). This needs to be traded off with the cpu overhead of
  //   spinning, so we use SPIN_THRESHOLD_NANOS which is what AbstractQueuedSynchronizer uses for

 * <li>Incremental crawling support with last-modified timestamp checking</li>
 * <li>Document expiration handling</li>
 * <li>Child URL extraction and queueing</li>
 * <li>Integration with Fess configuration and permission systems</li>
 * <li>Client selection based on URL patterns</li>
 * </ul>
 *
 * @see CrawlerThread
 * @see org.codelibs.fess.crawler.client.CrawlerClient
 */
public class FessCrawlerThread extends CrawlerThread {

 * - Scroll search for large result sets
 * - Document retrieval by ID
 * - Bulk document updates
 * - Search parameter serialization/deserialization for cookies
 * - Integration with search engines and logging systems
 */
public class SearchHelper {

    // ===================================================================================
    //                                                                            Constant