#### Utility: compare with alternatives


        There is always *some* alternative to adding a new feature to Guava, even if it's just
        forking Guava yourself.


        We want to see that new features have some significant advantage over the alternatives.
        These advantages can take

 * different signatures.
 */
@GwtCompatible
@J2ktIncompatible // Super-sourced
abstract class GwtFuturesCatchingSpecialization {
  /*
   * This server copy of the class is empty. The corresponding GWT copy contains alternative
   * versions of catching() and catchingAsync() with slightly different signatures from the ones
   * found in Futures.java.
   */

import org.jspecify.annotations.Nullable;

/**
 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible
public abstract class FinalizableWeakReference<T> extends WeakReference<T>

 * different signatures.
 */
@GwtCompatible
@J2ktIncompatible // Super-sourced
abstract class GwtFuturesCatchingSpecialization {
  /*
   * This server copy of the class is empty. The corresponding GWT copy contains alternative
   * versions of catching() and catchingAsync() with slightly different signatures from the ones
   * found in Futures.java.
   */

import org.jspecify.annotations.Nullable;

/**
 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible
public abstract class FinalizableWeakReference<T> extends WeakReference<T>

import org.jspecify.annotations.Nullable;

/**
 * Soft reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible
public abstract class FinalizableSoftReference<T> extends SoftReference<T>

/**
 * Helper class for managing related query configurations.
 * This class provides functionality to load, cache, and retrieve related queries
 * based on search terms and virtual hosts. Related queries are used to suggest
 * alternative or supplementary search terms to improve search results.
 */
public class RelatedQueryHelper extends AbstractConfigHelper {
    private static final Logger logger = LogManager.getLogger(RelatedQueryHelper.class);

    /**

 * ExecutionException}, the exception's {@linkplain #getCause() cause} comes from a failed task,
 * possibly run in another thread.
 *
 * <p>{@code UncheckedExecutionException} is intended as an alternative to {@code
 * ExecutionException} when the exception thrown by a task is an unchecked exception. However, it
 * may also wrap a checked exception in some cases.
 *

import jakarta.annotation.Resource;

/**
 * Service class for managing related query entities.
 * This service provides operations to retrieve, store, and delete related queries,
 * which are used to suggest alternative search terms to users.
 */
public class RelatedQueryService extends FessAppService {

    /**
     * Default constructor for RelatedQueryService.

    "EEE, dd MMM yyyy HH:mm:ss zzz",
    // RFC 850, obsoleted by RFC 1036 with any TZ.
    "EEEE, dd-MMM-yy HH:mm:ss zzz",
    // ANSI C's asctime() format
    "EEE MMM d HH:mm:ss yyyy",
    // Alternative formats:
    "EEE, dd-MMM-yyyy HH:mm:ss z",
    "EEE, dd-MMM-yyyy HH-mm-ss z",
    "EEE, dd MMM yy HH:mm:ss z",
    "EEE dd-MMM-yyyy HH:mm:ss z",
    "EEE dd MMM yyyy HH:mm:ss z",
    "EEE dd-MMM-yyyy HH-mm-ss z",