// nodes must have a single output.
        if (node->num_outputs() != 1) {
          return InvalidArgument(
              "When `num_opers` is set to -1, nodes referenced in `inputs` "
              "must have a single output. Node ",
              node->name(), " has ", node->num_outputs(),
              " outputs. Encountered while creating function '", fn_name, "'");
        }
      }
    }

      "Cannot add self-loop edge on node %s, as self-loops are not allowed. To construct a graph "
          + "that allows self-loops, call allowsSelfLoops(true) on the Builder.";
  static final String NOT_AVAILABLE_ON_UNDIRECTED =
      "Cannot call source()/target() on a EndpointPair from an undirected graph. Consider calling "
          + "adjacentNode(node) if you already have a node, or nodeU()/nodeV() if you don't.";

    assertThat(tree.keySet()).containsExactly("tree", "google").inOrder();
    assertThat(tree.get("google")).containsExactly(6, 2).inOrder();

    TreeMultimap<String, Integer> copy = TreeMultimap.create(tree);
    assertEquals(tree, copy);
    assertThat(copy.keySet()).containsExactly("google", "tree").inOrder();
    assertThat(copy.get("google")).containsExactly(2, 6).inOrder();
    assertEquals(Ordering.natural(), copy.keyComparator());

    return delegate().inDegree(node);
  }

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

  @Override
  public boolean hasEdgeConnecting(N nodeU, N nodeV) {
    return delegate().hasEdgeConnecting(nodeU, nodeV);
  }

  @Override
  public boolean hasEdgeConnecting(EndpointPair<N> endpoints) {
    return delegate().hasEdgeConnecting(endpoints);
  }

  @Override

 * with user-defined properties.
 *
 * <p>A {@code ValueGraph} built by this class has the following default properties:
 *
 * <ul>
 *   <li>does not allow self-loops
 *   <li>orders {@link ValueGraph#nodes()} in the order in which the elements were added (insertion
 *       order)
 * </ul>
 *
 * <p>{@code ValueGraph}s built by this class also guarantee that each collection-returning accessor

    assertThat(network.nodes()).containsExactly("A");
    assertThat(network.edges()).isEmpty();
  }

  @Test
  public void immutableNetworkBuilder_putEdgeFromNodes() {
    ImmutableNetwork<String, Integer> network =
        NetworkBuilder.directed().<String, Integer>immutable().addEdge("A", "B", 10).build();

    assertThat(network.nodes()).containsExactly("A", "B");

    long_wait_loop:
    if (remainingNanos >= SPIN_THRESHOLD_NANOS) {
      Waiter oldHead = waitersField;
      if (oldHead != Waiter.TOMBSTONE) {
        Waiter node = new Waiter();
        do {
          node.setNext(oldHead);
          if (casWaiters(oldHead, node)) {
            while (true) {
              OverflowAvoidingLockSupport.parkNanos(this, remainingNanos);

    /**
     * Returns an immutable list of all child nodes.
     *
     * @return list of child nodes, never {@code null}
     */
    @Nonnull
    List<XmlNode> children();

    /**
     * Returns the first child node with the specified name.
     *
     * @param name the name of the child node to find
     * @return the first matching child node, or {@code null} if none found
     */
    @Nullable

 * implementors</a>
 *
 * @author Joshua O'Madadhain
 * @author Jens Nyman
 * @param <N> Node parameter type
 * @since 23.0
 */
@Beta
@DoNotMock("Implement with a lambda, or use GraphBuilder to build a Graph with the desired edges")
public interface SuccessorsFunction<N> {

  /**

    // forward map ordered by currency (even for country values)
    assertThat(bimap.values()).containsExactly(Country.SWITZERLAND, Country.CHILE).inOrder();
    // backward map ordered by country
    assertThat(bimap.inverse().keySet())
        .containsExactly(Country.CHILE, Country.SWITZERLAND)
        .inOrder();