expectedTranspose.addEdge(N4, N3, E34);

    Network<Integer, String> transpose = transpose(directedGraph);
    assertThat(transpose).isEqualTo(expectedTranspose);
    assertThat(transpose(transpose)).isSameInstanceAs(directedGraph);
    AbstractNetworkTest.validateNetwork(transpose);

    assertThat(transpose.edgesConnecting(N1, N2)).isEmpty();
    assertThat(transpose.edgeConnectingOrNull(N1, N2)).isNull();

    expectedTranspose.addEdge(N4, N3, E34);

    Network<Integer, String> transpose = transpose(directedGraph);
    assertThat(transpose).isEqualTo(expectedTranspose);
    assertThat(transpose(transpose)).isSameInstanceAs(directedGraph);
    AbstractNetworkTest.validateNetwork(transpose);

    assertThat(transpose.edgesConnecting(N1, N2)).isEmpty();
    assertThat(transpose.edgeConnecting(N1, N2).isPresent()).isFalse();

    public int inDegree(N node) {
      return delegate().outDegree(node); // transpose
    }

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

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

    @Override

   * instance, {@code rowKeySet().iterator()} supports {@code remove()} but {@code
   * columnKeySet().iterator()} doesn't. With a transposed {@link HashBasedTable}, it's the other
   * way around.
   */
  public static <R extends @Nullable Object, C extends @Nullable Object, V extends @Nullable Object>
      Table<C, R, V> transpose(Table<R, C, V> table) {
    return (table instanceof TransposeTable)
        ? ((TransposeTable<R, C, V>) table).original

                  @Override
                  Table<String, Integer, Character> createTable() {
                    Table<Integer, String, Character> original = TreeBasedTable.create();
                    return Tables.transpose(original);
                  }
                })
            .named("TransposedTable.cellSet")
            .withFeatures(
                CollectionSize.ANY,
                CollectionFeature.REMOVE_OPERATIONS,

                  @Override
                  Table<String, Integer, Character> createTable() {
                    Table<Integer, String, Character> original = TreeBasedTable.create();
                    return Tables.transpose(original);
                  }
                })
            .named("TransposedTable.cellSet")
            .withFeatures(
                CollectionSize.ANY,
                CollectionFeature.REMOVE_OPERATIONS,

  /**
   * The HTTP <a href="http://tools.ietf.org/html/rfc6797#section-6.1">{@code
   * Strict-Transport-Security}</a> header field name.
   *
   * @since 15.0
   */
  public static final String STRICT_TRANSPORT_SECURITY = "Strict-Transport-Security";
  /**
   * The HTTP <a href="http://www.w3.org/TR/resource-timing/#cross-origin-resources">{@code