ComparableSubClass node8 = new ComparableSubClass(8);

    graph.addNode(node4);
    graph.addNode(node2);
    graph.addNode(node6);
    graph.addNode(node8);

    assertThat(graph.nodeOrder().comparator()).isEqualTo(Ordering.natural());
    assertThat(graph.nodes()).containsExactly(node2, node4, node6, node8).inOrder();
  }

  private static void addNodes(MutableGraph<Integer> graph) {

                + "{\"_source\":{\"type\":\"heartbeat\",\"instanceId\":\"node1@host1\",\"hostname\":\"host1\",\"name\":\"node1\",\"createdTime\":1000}},"
                + "{\"_source\":{\"type\":\"heartbeat\",\"instanceId\":\"node2@host2\",\"hostname\":\"host2\",\"name\":\"node2\",\"createdTime\":2000}}"
                + "]}}";
        final CoordinatorHelper helper = createCapturingHelper("node1@host1", null, null, createMockResponse(200, searchResponse));

    for (E key : keys) {
      LockGraphNode node = new LockGraphNode(getLockName(key));
      nodes.add(node);
      map.put(key, node);
    }
    // Pre-populate all allowedPriorLocks with nodes of smaller ordinal.
    for (int i = 1; i < numKeys; i++) {
      nodes.get(i).checkAcquiredLocks(Policies.THROW, nodes.subList(0, i));
    }
    // Pre-populate all disallowedPriorLocks with nodes of larger ordinal.

  TF_Operation *node1, *node2, *node3;
  NodeWithPlaceholderAttrHelper(func_graph.get(), s.get(), "node1", "v1",
                                &node1);
  NodeWithPlaceholderAttrHelper(func_graph.get(), s.get(), "node2", "v1",
                                &node2);
  NodeWithPlaceholderAttrHelper(func_graph.get(), s.get(), "node3", "v2",
                                &node3);

    GraphConnections<N, V> connectionsU = nodeConnections.get(nodeU);
    return (connectionsU != null) && connectionsU.successors().contains(nodeV);
  }

  private final @Nullable V edgeValueOrDefaultInternal(N nodeU, N nodeV, @Nullable V defaultValue) {
    GraphConnections<N, V> connectionsU = nodeConnections.get(nodeU);
    V value = (connectionsU == null) ? null : connectionsU.value(nodeV);

    MutableGraph<N> subgraph =
        (nodes instanceof Collection)
            ? GraphBuilder.from(graph).expectedNodeCount(((Collection) nodes).size()).build()
            : GraphBuilder.from(graph).build();
    for (N node : nodes) {
      subgraph.addNode(node);
    }
    for (N node : subgraph.nodes()) {
      for (N successorNode : graph.successors(node)) {

   * given nodes is not present in this network.
   *
   * @since 33.1.0
   */
  protected final <T> Set<T> nodePairInvalidatableSet(Set<T> set, N nodeU, N nodeV) {
    return InvalidatableSet.of(
        set,
        () -> nodes().contains(nodeU) && nodes().contains(nodeV),
        () -> String.format(NODE_PAIR_REMOVED_FROM_GRAPH, nodeU, nodeV));
  }

        // We already know that nodeU equals other.nodeU. Combined with the earlier statement,
        // and the transitive property of equality, this implies that nodeU equals nodeV.
        // If nodeU equals nodeV, condition1 == condition2, so checking condition1 is sufficient.
        return nodeV().equals(other.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);

  /**

    // whatever ordering the network's nodes do, so ImmutableSortedMap is unnecessary even if the
    // input nodes are sorted.
    ImmutableMap.Builder<N, NetworkConnections<N, E>> nodeConnections = ImmutableMap.builder();
    for (N node : network.nodes()) {
      nodeConnections.put(node, connectionsOf(network, node));
    }
    return nodeConnections.buildOrThrow();
  }