public static <V extends @Nullable Object> ListenableFuture<V> immediateCancelledFuture() {
    ListenableFuture<Object> instance = ImmediateCancelledFuture.INSTANCE;
    if (instance != null) {
      return (ListenableFuture<V>) instance;
    }
    return new ImmediateCancelledFuture<>();
  }

  /**

        }
      };

  enum NullListener implements RemovalListener<Object, Object> {
    INSTANCE;

    @Override
    public void onRemoval(RemovalNotification<Object, Object> notification) {}
  }

  enum OneWeigher implements Weigher<Object, Object> {
    INSTANCE;

    @Override
    public int weigh(Object key, Object value) {
      return 1;
    }
  }

        }
      };

  enum NullListener implements RemovalListener<Object, Object> {
    INSTANCE;

    @Override
    public void onRemoval(RemovalNotification<Object, Object> notification) {}
  }

  enum OneWeigher implements Weigher<Object, Object> {
    INSTANCE;

    @Override
    public int weigh(Object key, Object value) {
      return 1;
    }
  }

    }

    /**
     * Returns the Fess configuration instance.
     *
     * @return the Fess configuration
     */
    @Override
    public FessConfig getFessConfig() {
        return fessConfig;
    }

    /**
     * Returns the logger instance for this class.
     *
     * @return the logger instance
     */
    @Override
    public Logger getLogger() {

            K, V, StrongKeyStrongValueEntry<K, V>, StrongKeyStrongValueSegment<K, V>> {
      private static final Helper<?, ?> INSTANCE = new Helper<>();

      @SuppressWarnings("unchecked")
      static <K, V> Helper<K, V> instance() {
        return (Helper<K, V>) INSTANCE;
      }

      @Override
      public Strength keyStrength() {
        return Strength.STRONG;
      }

      @Override

        return Constants.TRUE.equalsIgnoreCase(getSystemProperty(key, defaultValue ? Constants.TRUE : Constants.FALSE));
    }

    default void setSystemPropertyAsBoolean(final String key, final boolean value) {
        setSystemProperty(key, value ? Constants.TRUE : Constants.FALSE);
    }

    /**
     * Creates and returns a new instance of {@link ArrayDeque}.
     *
     * @param <E> the element type of {@link ArrayDeque}
     * @return a new instance of {@link ArrayDeque}
     * @see ArrayDeque#ArrayDeque()
     */
    public static <E> ArrayDeque<E> newArrayDeque() {
        return new ArrayDeque<>();
    }

    /**
     * Creates and returns a new instance of {@link ArrayDeque}.
     *

            responseData.setUrl(url);
            responseData.setCharSet(contentEncoding);
            if (httpRequest instanceof HttpHead) {
                responseData.setMethod(Constants.HEAD_METHOD);
            } else {
                responseData.setMethod(Constants.GET_METHOD);
            }
            responseData.setHttpStatusCode(httpStatusCode);
            for (final Header header : response.getAllHeaders()) {

   * object that equals a set member, but isn't the same instance. This behavior is similar to the
   * way {@code IdentityHashMap} handles key lookups.
   *
   * @since 8.0
   */
  public static <E extends @Nullable Object> Set<E> newIdentityHashSet() {
    return Collections.newSetFromMap(Maps.newIdentityHashMap());
  }

  /**
   * Creates an empty {@code CopyOnWriteArraySet} instance.
   *

    memory!

    The best practice in OkHttp 3 is to create a single OkHttpClient instance
    and share it throughout the application. Requests that needs a customized
    client should call `OkHttpClient.newBuilder()` on that shared instance.
    This allows customization without the drawbacks of separate connection
    pools.