* This class provides a default way to manage delays between crawler operations.
 * It allows setting delays before processing, after processing, when no URLs are in the queue,
 * and when waiting for new URLs.
 * The delays are configurable via constructor parameters.
 *
 */
public class DefaultIntervalController extends AbstractIntervalController {

    /** Delay in milliseconds after processing a URL */

 * It supports password-protected PDFs and can extract embedded documents and annotations.
 *
 * <p>The extractor runs text extraction in a separate thread with a configurable timeout
 * to prevent hanging on problematic PDF files. It also extracts metadata from the PDF
 * document and includes it in the extraction result.
 *
 * <p>Features:
 * <ul>

- **License Headers**: Required (Apache 2.0) - use `mvn license:format`
- **Logging**: Log4j2 - `src/main/resources/log4j2.xml`
- **i18n**: All user-facing strings in `fess_label_*.properties`
- **Default Port**: 8080 (configurable via `fess.port` system property)
- **Log Location**: `target/fess-logs/` (dev), `/var/log/fess/` (prod)
- **Admin Login**: `admin/admin`

## Log Message Guidelines

 *
 * <p>Features:
 * <ul>
 *   <li>Structured text extraction with key-value pairs</li>
 *   <li>Top-level field extraction as metadata</li>
 *   <li>Nested structure flattening with configurable depth</li>
 *   <li>Array element extraction</li>
 *   <li>Configurable field separator and array formatting</li>
 * </ul>
 */
public class JsonExtractor extends AbstractExtractor {
    /** Logger instance for this class. */

 *   <li>Heading structure extraction</li>
 *   <li>Link URL extraction</li>
 *   <li>Code block content extraction</li>
 *   <li>Clean text conversion from Markdown</li>
 *   <li>Configurable encoding</li>
 * </ul>
 */
public class MarkdownExtractor extends AbstractExtractor {
    /** Logger instance for this class. */
    private static final Logger logger = LogManager.getLogger(MarkdownExtractor.class);

import org.opensearch.index.query.QueryBuilders;

/**
 * Query command implementation for handling fuzzy search queries.
 * This class converts Lucene FuzzyQuery objects into OpenSearch fuzzy query builders,
 * supporting configurable fuzzy matching parameters like edit distance and expansions.
 *
 */
public class FuzzyQueryCommand extends QueryCommand {
    private static final Logger logger = LogManager.getLogger(FuzzyQueryCommand.class);

    /**

import org.opensearch.index.query.QueryBuilders;

/**
 * Query command for handling wildcard queries.
 * Converts Lucene WildcardQuery objects to OpenSearch QueryBuilder objects,
 * supporting wildcard pattern matching with configurable case sensitivity.
 */
public class WildcardQueryCommand extends QueryCommand {

    /**
     * Default constructor.
     */
    public WildcardQueryCommand() {
        super();
    }

 *   <li>Header row detection and extraction</li>
 *   <li>Column name to data value association</li>
 *   <li>Quoted field handling</li>
 *   <li>Column names as metadata</li>
 *   <li>Configurable encoding and row limits</li>
 * </ul>
 */
public class CsvExtractor extends AbstractExtractor {
    /** Logger instance for this class. */
    private static final Logger logger = LogManager.getLogger(CsvExtractor.class);

 * reducing the overhead of repeated cipher initialization. It supports both string-based keys
 * and {@link Key} objects, with configurable algorithms and character encodings.
 * </p>
 * <p>
 * <strong>Key Features:</strong>
 * </p>
 * <ul>
 * <li>Thread-safe cipher pooling using {@link ConcurrentLinkedQueue}</li>
 * <li>Configurable encryption algorithms (default: Blowfish)</li>
 * <li>Proper charset handling for key generation (UTF-8 by default)</li>

Where the spec is ambiguous, OkHttp follows modern user agents such as popular Browsers or common HTTP Libraries.

OkHttp is principled and avoids being overly configurable, especially when such configuration is
to workaround a buggy server, test invalid scenarios or that contradict the relevant RFC.
Other HTTP libraries exist that fill that gap allowing extensive customisation including potentially