* This class is used to encapsulate the header information for HTTP requests.
 * It provides methods to get and set the name and value of the header,
 * as well as a method to validate the header.
 *
 * <p>Example usage:</p>
 * <pre>
 *     RequestHeader header = new RequestHeader("Content-Type", "application/json");
 *     String name = header.getName();
 *     String value = header.getValue();

 *
 * <p>The conversion is performed by iterating through the conversion map and applying
 * each replacement rule sequentially. The order of the rules in the map is preserved
 * during the conversion process.</p>
 *
 * <p>Example usage:</p>
 *
 * <pre>{@code
 * UrlConvertHelper helper = new UrlConvertHelper();
 * helper.add("old-domain.com", "new-domain.com");
 * String convertedUrl = helper.convert("http://old-domain.com/path");

    /**
     * Regular expression pattern to match the charset attribute in the meta tag of HTML documents.
     * The pattern captures the charset value specified in the content attribute of the meta tag.
     * Example: <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
     */
    protected Pattern metaCharsetPattern = Pattern.compile("<meta.*content\\s*=\\s*['\"].*;\\s*charset=([\\w\\d\\-_]*)['\"]\\s*/?>",

 * The class also utilizes ICU4J's {@link com.ibm.icu.text.Transliterator} to convert full-width characters
 * to half-width and to convert any characters to lowercase, ensuring consistency in the output.
 * </p>
 *
 * <p>
 * Example:
 * For the input "キャ", the converter might return a list containing "kya".
 * For the input "ジュ", the converter might return a list containing "zyu", "ju", and "jyu".
 * </p>
 *
 */

 * maximum length of analyzed content.</p>
 *
 * <p>Methods in this class may throw SuggesterException in case of failures during the parsing process.</p>
 *
 * <p>Usage example:</p>
 * <pre>
 * {@code
 * DefaultContentsParser parser = new DefaultContentsParser();
 * SuggestItem item = parser.parseSearchWords(words, readings, fields, tags, roles, score, readingConverter, normalizer, analyzer, langs);

 * </ol>
 *
 * <p>The crawler can be configured with various parameters, such as the number of threads,
 * the maximum depth of crawling, and URL filters.
 *
 * <p>Example usage:
 * <pre>
 *   Crawler crawler = new Crawler();
 *   crawler.addUrl("http://example.com/");
 *   crawler.execute();
 *   crawler.close();
 * </pre>
 */
public class Crawler implements Runnable, AutoCloseable {

 *   <li>{@link DataService} - The service for managing access results.</li>
 * </ul>
 *
 * <p>Each parameter is stored in a ThreadLocal variable to ensure thread safety.</p>
 *
 * <p>Usage example:</p>
 * <pre>
 * {@code
 * UrlQueue<?> urlQueue = CrawlingParameterUtil.getUrlQueue();
 * CrawlingParameterUtil.setUrlQueue(newUrlQueue);
 *
 * CrawlerContext context = CrawlingParameterUtil.getCrawlerContext();

        final InputStream in = ResourceUtil.getResourceAsStream("extractor/test_pass.pdf");
        final Map<String, String> params = new HashMap<String, String>();
        params.put(ExtractData.URL, "http://example.com/test_pass.pdf");
        final String content = pdfExtractorForPdfPassword.getText(in, params).getContent();
        CloseableUtil.closeQuietly(in);
        logger.info(content);
        assertTrue(content.contains("テスト"));

 *   <li>Creating the response from the search results.</li>
 * </ul>
 *
 * <p>Example usage:</p>
 * <pre>
 * SuggestRequest suggestRequest = new SuggestRequest();
 * suggestRequest.setIndex("my_index");
 * suggestRequest.setQuery("example query");
 * suggestRequest.setSize(5);
 * suggestRequest.addTag("tag1");
 * suggestRequest.addRole("role1");

 * </p>
 *
 * <p>
 * The class uses JCIFS properties to configure the SMB connection.
 * </p>
 *
 * <p>
 * Usage example:
 * </p>
 *
 * <pre>
 * {@code
 * SmbClient smbClient = new SmbClient();
 * smbClient.init();
 * ResponseData responseData = smbClient.doGet("smb://example.com/share/file.txt");
 * // Process the responseData
 * smbClient.close();
 * }
 * </pre>
 *
 * @author shinsuke