*       order)
 * </ul>
 *
 * <p>{@code ValueGraph}s built by this class also guarantee that each collection-returning accessor
 * returns a <b>(live) unmodifiable view</b>; see <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#accessor-behavior">the external
 * documentation</a> for details.
 *
 * <p>Examples of use:
 *
 * {@snippet :
 * // Building a mutable value graph

 *       order)
 * </ul>
 *
 * <p>{@code Graph}s built by this class also guarantee that each collection-returning accessor
 * returns a <b>(live) unmodifiable view</b>; see <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#accessor-behavior">the external
 * documentation</a> for details.
 *
 * <p>Examples of use:
 *
 * {@snippet :
 * // Building a mutable graph

 *       order)
 * </ul>
 *
 * <p>{@code ValueGraph}s built by this class also guarantee that each collection-returning accessor
 * returns a <b>(live) unmodifiable view</b>; see <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#accessor-behavior">the external
 * documentation</a> for details.
 *
 * <p>Examples of use:
 *
 * {@snippet :
 * // Building a mutable value graph

                      Iterators.transform(
                          // filter out 'node' from successors (already covered by predecessors,
                          // above)
                          Sets.difference(graph.successors(node), ImmutableSet.of(node)).iterator(),
                          (N successor) -> EndpointPair.ordered(node, successor))));
            } else {

 * which has a method {@code getChildren()} that retrieves its successors in a graph:
 *
 * {@snippet :
 * someGraphAlgorithm(startNode, MyNode::getChildren);
 * }
 *
 * <p>If you have some other mechanism for returning the successors of a node, or one that doesn't
 * return an {@code Iterable<? extends N>}, then you can use a lambda to perform a more general

  @Override
  public Set<N> successors() {
    return Collections.unmodifiableSet(successorsMultiset().elementSet());
  }

  private Multiset<N> successorsMultiset() {
    Multiset<N> successors = getReference(successorsReference);
    if (successors == null) {
      successors = HashMultiset.create(outEdgeMap.values());
      successorsReference = new SoftReference<>(successors);
    }
    return successors;
  }

  @Override
  public Set<N> successors() {
    return Collections.unmodifiableSet(successorsMultiset().elementSet());
  }

  private Multiset<N> successorsMultiset() {
    Multiset<N> successors = getReference(successorsReference);
    if (successors == null) {
      successors = HashMultiset.create(outEdgeMap.values());
      successorsReference = new SoftReference<>(successors);
    }
    return successors;
  }

 * which has a method {@code getChildren()} that retrieves its successors in a graph:
 *
 * {@snippet :
 * someGraphAlgorithm(startNode, MyNode::getChildren);
 * }
 *
 * <p>If you have some other mechanism for returning the successors of a node, or one that doesn't
 * return an {@code Iterable<? extends N>}, then you can use a lambda to perform a more general

    return delegate().adjacentNodes(node);
  }

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

  @Override
  public Set<N> successors(N node) {
    return delegate().successors(node);
  }

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

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

    return delegate().adjacentNodes(node);
  }

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

  @Override
  public Set<N> successors(N node) {
    return delegate().successors(node);
  }

  @Override
  public Set<EndpointPair<N>> incidentEdges(N node) {
    return delegate().incidentEdges(node);
  }

  @Override
  public int degree(N node) {