validateEndpoints(endpoints);
    return edgeConnectingOrNull(endpoints.nodeU(), endpoints.nodeV());
  }

  @Override
  public boolean hasEdgeConnecting(N nodeU, N nodeV) {
    checkNotNull(nodeU);
    checkNotNull(nodeV);
    return nodes().contains(nodeU) && successors(nodeU).contains(nodeV);
  }

  @Override
  public boolean hasEdgeConnecting(EndpointPair<N> endpoints) {

  }

  @Override
  public boolean hasEdgeConnecting(N nodeU, N nodeV) {
    checkNotNull(nodeU);
    checkNotNull(nodeV);
    return nodes().contains(nodeU) && successors(nodeU).contains(nodeV);
  }

  @Override
  public boolean hasEdgeConnecting(EndpointPair<N> endpoints) {
    checkNotNull(endpoints);
    if (!isOrderingCompatible(endpoints)) {
      return false;

    checkNotNull(nodeU);
    checkNotNull(nodeV);
    return nodes().contains(nodeU) && successors(nodeU).contains(nodeV);
  }

  @Override
  public boolean hasEdgeConnecting(EndpointPair<N> endpoints) {
    checkNotNull(endpoints);
    if (!isOrderingCompatible(endpoints)) {
      return false;
    }
    N nodeU = endpoints.nodeU();
    N nodeV = endpoints.nodeV();

        return AbstractValueGraph.this.degree(node);
      }

      @Override
      public int inDegree(N node) {
        return AbstractValueGraph.this.inDegree(node);
      }

      @Override
      public int outDegree(N node) {
        return AbstractValueGraph.this.outDegree(node);
      }
    };
  }

  @Override
  public Optional<V> edgeValue(N nodeU, N nodeV) {

  // StartTime before the system will actively try to mark it failed and kill associated containers.
  // Value must be a positive integer.
  // +optional
  optional int64 activeDeadlineSeconds = 5;

  // NodeSelector is a selector which must be true for the carp to fit on a node.
  // Selector which must match a node's labels for the carp to be scheduled on that node.

  // https://git.k8s.io/enhancements/keps/sig-node/688-pod-overhead/README.md
  // +optional
  optional Overhead overhead = 3;

  // scheduling holds the scheduling constraints to ensure that pods running
  // with this RuntimeClass are scheduled to nodes that support it.
  // If scheduling is nil, this RuntimeClass is assumed to be supported by all
  // nodes.
  // +optional
  optional Scheduling scheduling = 4;
}

- **Node**
  - [alpha] Publish node performance dashboard at http://node-perf-dash.k8s.io/#/builds ([docs](https://github.com/kubernetes/contrib/blob/master/node-perf-dash/README.md)) ([kubernetes/features#83](https://github.com/kubernetes/enhancements/issues/83))

  int outDegree(N node);

  /**
   * Returns true if there is an edge that directly connects {@code nodeU} to {@code nodeV}. This is
   * equivalent to {@code nodes().contains(nodeU) && successors(nodeU).contains(nodeV)}.
   *
   * <p>In an undirected graph, this is equal to {@code hasEdgeConnecting(nodeV, nodeU)}.
   *
   * @since 23.0
   */
  @Override
  boolean hasEdgeConnecting(N nodeU, N nodeV);

  /**

  int outDegree(N node);

  /**
   * Returns true if there is an edge that directly connects {@code nodeU} to {@code nodeV}. This is
   * equivalent to {@code nodes().contains(nodeU) && successors(nodeU).contains(nodeV)}.
   *
   * <p>In an undirected graph, this is equal to {@code hasEdgeConnecting(nodeV, nodeU)}.
   *
   * @since 23.0
   */
  @Override
  boolean hasEdgeConnecting(N nodeU, N nodeV);

  /**

// Creates a new eager Executor. Nodes in one executor are guaranteed to be
// executed in sequence. Assigning nodes to different executors allows executing
// nodes in parallel.
// in_flight_nodes_limit: when is_async is true, this value controls the
// maximum number of in flight async nodes. Enqueuing of additional async ops
// after the limit is reached blocks until some inflight nodes finishes.