*  Fix: `OkApacheClient` now allows an empty `PUT` and `POST`.
 *  Fix: Websockets no longer rebuffer socket streams.
 *  Fix: Websockets are now better at handling close frames.
 *  Fix: Content type matching is now case insensitive.
 *  Fix: `Vary` headers are not lost with `android.net.http.HttpResponseCache`.
 *  Fix: HTTP/2 wasn't enforcing stream timeouts when writing the underlying
    connection. Now it is.

import java.io.File;
import java.io.FilenameFilter;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;

/**
 * File name filter that only accepts files matching a regular expression. This class is thread-safe
 * and immutable.
 *
 * @author Apple Chow
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class PatternFilenameFilter implements FilenameFilter {

 * This class provides functionality to load, cache, and retrieve related content
 * based on search queries and virtual host configurations. It supports both exact
 * term matching and regex pattern matching for flexible content association.
 */
public class RelatedContentHelper extends AbstractConfigHelper {

    /**
     * Default constructor for RelatedContentHelper.

     * pagination information including page numbers and result counts.
     *
     * @param fileConfigPager the pager containing search criteria and pagination settings
     * @return a list of file configurations matching the criteria
     */
    public List<FileConfig> getFileConfigList(final FileConfigPager fileConfigPager) {

        final PagingResultBean<FileConfig> fileConfigList = fileConfigBhv.selectPage(cb -> {

import static com.google.common.base.Preconditions.checkNotNull;

import java.util.Map;
import org.jspecify.annotations.Nullable;

/**
 * A {@link MapIteratorCache} that adds additional caching. In addition to the caching provided by
 * {@link MapIteratorCache}, this structure caches values for the two most recently retrieved keys.
 *
 * @author James Sexton
 */
final class MapRetrievalCache<K, V> extends MapIteratorCache<K, V> {

    public Integer crudMode;

    /** URL expression pattern to match documents for boosting */
    @Required
    @Size(max = 10000)
    public String urlExpr;

    /** Boost expression to apply to matching documents */
    @Required
    @Size(max = 10000)
    public String boostExpr;

    /** Sort order for displaying boost configurations */
    @Required
    @Min(value = 0)
    @Max(value = 2147483647)

    }

    /**
     * Retrieves related queries for a given search term.
     * The search is performed using the current virtual host context and
     * the query term is converted to lowercase for case-insensitive matching.
     *
     * @param query the search term to find related queries for
     * @return an array of related query strings, or empty array if none found
     */
    public String[] getRelatedQueries(final String query) {

    /**
     * Retrieves a paginated list of related content entities.
     *
     * @param relatedContentPager the pager object containing pagination and search parameters
     * @return a list of RelatedContent entities matching the specified criteria
     */
    public List<RelatedContent> getRelatedContentList(final RelatedContentPager relatedContentPager) {

        context.addHighlightedQuery(text);
        return QueryBuilders.termQuery(field, text).boost(boost);
    }

    /**
     * Converts a term query to a wildcard query for URL field matching.
     *
     * @param fessConfig the Fess configuration
     * @param context the query context
     * @param termQuery the term query to convert
     * @param boost the boost value to apply

    /**
     * Gets a paginated list of boost document rules.
     * @param boostDocumentRulePager The pager with search criteria and pagination settings.
     * @return List of boost document rules matching the criteria.
     */
    public List<BoostDocumentRule> getBoostDocumentRuleList(final BoostDocPager boostDocumentRulePager) {