* @return The value of found property. (NotNull: if not found, exception)
     * @throws ConfigPropertyNotFoundException When the property is not found.
     */
    String get(String propertyKey);

    /**
     * Is the property true?
     * @param propertyKey The key of the property which is boolean type. (NotNull)
     * @return The determination, true or false. (if not found, exception)

            return escapeValue(key);
        }
        if (keyObj instanceof final Number key) {
            return key.toString();
        }
        return "-";
    }

    /**
     * Generates a cache key from a crawler object.
     *
     * @param keyObj the crawler object to generate key for
     * @return Optional cache key string, empty if object type not supported
     */

	if err := target.init(); err != nil {
		return false, err
	}
	return target.isActive()
}

func (target *PostgreSQLTarget) isActive() (bool, error) {
	if err := target.db.Ping(); err != nil {
		if IsConnErr(err) {
			return false, store.ErrNotConnected
		}
		return false, err
	}
	return true, nil
}

  }

  @Override
  public Multimap<K, V> unfiltered() {
    return unfiltered;
  }

  @Override
  public Predicate<? super Entry<K, V>> entryPredicate() {
    return predicate;
  }

  @Override
  public int size() {
    return entries().size();
  }

  private boolean satisfies(@ParametricNullness K key, @ParametricNullness V value) {
    return predicate.apply(immutableEntry(key, value));
  }

     */
    protected static Date toDate(final Object src, final String pattern, final Locale locale) {
        if (src == null) {
            return null;
        }
        if (src.getClass() == Date.class) {
            return (Date) src;
        }
        if (src instanceof Date) {
            return new Date(((Date) src).getTime());
        }
        if (src instanceof Calendar) {

      return false;
    }
    EndpointPair<?> endpointPair = (EndpointPair<?>) obj;

    if (graph.isDirected() != endpointPair.isOrdered()) {
      return false;
    }

    if (graph.isDirected()) {
      Object source = endpointPair.source();
      Object target = endpointPair.target();
      return (node.equals(source) && successorsOrEmpty(node).contains(target))

    }
    return adjacentNodes;
  }

  @Override
  public Set<E> edgesConnecting(N node) {
    return new MultiEdgesConnecting<E>(incidentEdgeMap, node) {
      @Override
      public int size() {
        return adjacentNodesMultiset().count(node);
      }
    };
  }

  @Override
  public @Nullable N removeInEdge(E edge, boolean isSelfLoop) {
    if (!isSelfLoop) {
      return removeOutEdge(edge);
    }

    if (result != null) {
      return result;
    } else {
      return defaultValue;
    }
  }

  private transient @Nullable ImmutableSet<Entry<K, V>> cachedEntrySet = null;

  @Override
  public final ImmutableSet<Entry<K, V>> entrySet() {
    if (cachedEntrySet != null) {
      return cachedEntrySet;
    }
    return cachedEntrySet = createEntrySet();
  }

    //                                                                             =======
    @Override
    public RelatedContentDbm asDBMeta() {
        return RelatedContentDbm.getInstance();
    }

    @Override
    public String asTableDbName() {
        return "related_content";
    }

    // ===================================================================================

     *
     * @return the HTTP URL for the OpenSearch server
     */
    public static String getFesenHttpUrl() {
        final String url = SystemUtil.getSearchEngineHttpAddress();
        if (url != null) {
            return url;
        }
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        return fessConfig.getFesenHttpUrl();
    }

    /**