return endpoints.isOrdered() == this.isDirected();
  }

  @Override
  public final boolean equals(@CheckForNull Object obj) {
    if (obj == this) {
      return true;
    }
    if (!(obj instanceof Network)) {
      return false;
    }
    Network<?, ?> other = (Network<?, ?>) obj;

    return isDirected() == other.isDirected()
        && nodes().equals(other.nodes())

      }

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

      @Override
      public boolean isDirected() {
        return AbstractValueGraph.this.isDirected();
      }

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

      @Override

   * implementation.
   */
  @Override
  protected long edgeCount() {
    return delegate().edges().size();
  }

  @Override
  public boolean isDirected() {
    return delegate().isDirected();
  }

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

  @Override
  public ElementOrder<N> nodeOrder() {

   * <p>The "queryable" properties are those that are exposed through the {@link Graph} interface,
   * such as {@link Graph#isDirected()}. Other properties, such as {@link #expectedNodeCount(int)},
   * are not set in the new builder.
   */
  public static <N> GraphBuilder<N> from(Graph<N> graph) {
    return new GraphBuilder<N>(graph.isDirected())
        .allowsSelfLoops(graph.allowsSelfLoops())
        .nodeOrder(graph.nodeOrder())

    Graph<?> other = (Graph<?>) obj;

    return isDirected() == other.isDirected()
        && nodes().equals(other.nodes())
        && edges().equals(other.edges());
  }

  @Override
  public final int hashCode() {
    return edges().hashCode();
  }

  /** Returns a string representation of this graph. */
  @Override
  public String toString() {
    return "isDirected: "
        + isDirected()

    return nodeConnections.unmodifiableKeySet();
  }

  @Override
  public Set<E> edges() {
    return edgeToReferenceNode.unmodifiableKeySet();
  }

  @Override
  public boolean isDirected() {
    return isDirected;
  }

  @Override
  public boolean allowsParallelEdges() {
    return allowsParallelEdges;
  }

  @Override
  public boolean allowsSelfLoops() {
    return allowsSelfLoops;

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

  @Override
  public Set<E> edges() {
    return delegate().edges();
  }

  @Override
  public boolean isDirected() {
    return delegate().isDirected();
  }

  @Override
  public boolean allowsParallelEdges() {
    return delegate().allowsParallelEdges();
  }

  @Override
  public boolean allowsSelfLoops() {

        GraphBuilder.directed()
            .allowsSelfLoops(true)
            .nodeOrder(ElementOrder.<String>natural())
            .immutable()
            .build();

    assertThat(emptyGraph.isDirected()).isTrue();
    assertThat(emptyGraph.allowsSelfLoops()).isTrue();
    assertThat(emptyGraph.nodeOrder()).isEqualTo(ElementOrder.<String>natural());
  }

  /**

        NetworkBuilder.directed()
            .allowsSelfLoops(true)
            .nodeOrder(ElementOrder.<String>natural())
            .<String, Integer>immutable()
            .build();

    assertThat(emptyNetwork.isDirected()).isTrue();
    assertThat(emptyNetwork.allowsSelfLoops()).isTrue();
    assertThat(emptyNetwork.nodeOrder()).isEqualTo(ElementOrder.<String>natural());
  }

  /**

        ValueGraphBuilder.directed()
            .allowsSelfLoops(true)
            .nodeOrder(ElementOrder.<String>natural())
            .<String, Integer>immutable()
            .build();

    assertThat(emptyGraph.isDirected()).isTrue();
    assertThat(emptyGraph.allowsSelfLoops()).isTrue();
    assertThat(emptyGraph.nodeOrder()).isEqualTo(ElementOrder.<String>natural());
  }

  /**