newBuilder.nodeOrder = checkNotNull(nodeOrder);
    return newBuilder;
  }

  /**
   * Specifies the order of iteration for the elements of {@link Graph#edges()}, {@link
   * Graph#adjacentNodes(Object)}, {@link Graph#predecessors(Object)}, {@link
   * Graph#successors(Object)} and {@link Graph#incidentEdges(Object)}.
   *
   * <p>The default value is {@link ElementOrder#unordered() unordered} for mutable graphs. For

      return network.nodeOrder();
    }

    @Override
    public ElementOrder<E> edgeOrder() {
      return network.edgeOrder();
    }

    @Override
    public Set<N> adjacentNodes(N node) {
      return network.adjacentNodes(node);
    }

    @Override
    public Set<N> predecessors(N node) {
      return network.predecessors(node);
    }

    @Override
    public Set<N> successors(N node) {

   */
  @Override
  Set<N> adjacentNodes(N node);

  /**
   * Returns a live view of all nodes in this graph adjacent to {@code node} which can be reached by
   * traversing {@code node}'s incoming edges <i>against</i> the direction (if any) of the edge.
   *
   * <p>In an undirected graph, this is equivalent to {@link #adjacentNodes(Object)}.
   *

    return graph.isDirected()
        ? DirectedGraphConnections.ofImmutable(node, graph.incidentEdges(node), edgeValueFn)
        : UndirectedGraphConnections.ofImmutable(
            Maps.asMap(graph.adjacentNodes(node), edgeValueFn));
  }

  @Override
  BaseGraph<N> delegate() {
    return backingGraph;
  }

  /**
   * A builder for creating {@link ImmutableGraph} instances, especially {@code static final}

    newBuilder.nodeOrder = checkNotNull(nodeOrder);
    return newBuilder;
  }

  /**
   * Specifies the order of iteration for the elements of {@link ValueGraph#edges()}, {@link
   * ValueGraph#adjacentNodes(Object)}, {@link ValueGraph#predecessors(Object)}, {@link
   * ValueGraph#successors(Object)} and {@link ValueGraph#incidentEdges(Object)}.
   *

      @Override
      public ElementOrder<N> incidentEdgeOrder() {
        return AbstractValueGraph.this.incidentEdgeOrder();
      }

      @Override
      public Set<N> adjacentNodes(N node) {
        return AbstractValueGraph.this.adjacentNodes(node);
      }

      @Override
      public Set<N> predecessors(N node) {
        return AbstractValueGraph.this.predecessors(node);
      }

      @Override

    N nodeV = requireNonNull(nodeConnections.get(nodeU)).adjacentNode(edge);
    return EndpointPair.of(this, nodeU, nodeV);
  }

  @Override
  public Set<N> adjacentNodes(N node) {
    return nodeInvalidatableSet(checkedConnections(node).adjacentNodes(), node);
  }

  @Override
  public Set<E> edgesConnecting(N nodeU, N nodeV) {

    return new DirectedGraphConnections<>(
        adjacentNodeValues,
        orderedNodeConnectionsBuilder.build(),
        predecessorCount,
        successorCount);
  }

  @Override
  public Set<N> adjacentNodes() {
    if (orderedNodeConnections == null) {
      return Collections.unmodifiableSet(adjacentNodeValues.keySet());
    } else {
      return new AbstractSet<N>() {
        @Override

   */
  Set<N> adjacentNodes(N node);

  /**
   * Returns a live view of all nodes in this network adjacent to {@code node} which can be reached
   * by traversing {@code node}'s incoming edges <i>against</i> the direction (if any) of the edge.
   *
   * <p>In an undirected network, this is equivalent to {@link #adjacentNodes(Object)}.
   *

      }

      @Override
      public boolean allowsSelfLoops() {
        return AbstractNetwork.this.allowsSelfLoops();
      }

      @Override
      public Set<N> adjacentNodes(N node) {
        return AbstractNetwork.this.adjacentNodes(node);
      }

      @Override
      public Set<N> predecessors(N node) {
        return AbstractNetwork.this.predecessors(node);
      }

      @Override