ElementOrder<E> edgeOrder();

  //
  // Element-level accessors
  //

  /**
   * Returns a live view of the nodes which have an incident edge in common with {@code node} in
   * this graph.
   *
   * <p>This is equal to the union of {@link #predecessors(Object)} and {@link #successors(Object)}.
   *

Cleanup_ for a safe and fast upgrade.


Backwards-Incompatible Changes
------------------------------

#### OkHttpClient final methods

`OkHttpClient` has 26 accessors like `interceptors()` and `writeTimeoutMillis()` that were non-final
in OkHttp 3.x and are final in 4.x. These were made non-final for use with mocking frameworks like

@GwtCompatible
public interface Table<
    R extends @Nullable Object, C extends @Nullable Object, V extends @Nullable Object> {
  // TODO(jlevy): Consider adding methods similar to ConcurrentMap methods.

  // Accessors

  /**
   * Returns {@code true} if the table contains a mapping with the specified row and column keys.
   *
   * @param rowKey key of row to search for
   * @param columnKey key of column to search for
   */

    ```kotlin
    @StartStop val server = MockWebServer()
    ```

 *  Breaking: Don't automatically start `MockWebServer` after calls to accessors like `port`. Now
    these accessors will throw an `IllegalStateException` if the service has not yet been started.

 *  Breaking: Rename `RecordedRequest.path` to `RecordedRequest.target`. (This property is

   * to determine whether {@code copyOf} implementations should make an explicit copy to avoid
   * memory leaks.
   */
  boolean isPartialView() {
    return map.isPartialView();
  }

  // accessors

  @Override
  public boolean containsKey(@Nullable Object key) {
    return map.containsKey(key);
  }

  @Override
  public boolean containsValue(@Nullable Object value) {

  final Supplier<? extends Map<C, V>> factory;

  StandardTable(Map<R, Map<C, V>> backingMap, Supplier<? extends Map<C, V>> factory) {
    this.backingMap = backingMap;
    this.factory = factory;
  }

  // Accessors

  @Override
  public boolean contains(@Nullable Object rowKey, @Nullable Object columnKey) {
    return rowKey != null && columnKey != null && super.contains(rowKey, columnKey);
  }

  @Override

      assertThat(network.adjacentNodes(node)).isEqualTo(asGraph.adjacentNodes(node));
      assertThat(network.predecessors(node)).isEqualTo(asGraph.predecessors(node));
      assertThat(network.successors(node)).isEqualTo(asGraph.successors(node));

      int selfLoopCount = network.edgesConnecting(node, node).size();
      assertThat(network.incidentEdges(node).size() + selfLoopCount)
          .isEqualTo(network.degree(node));

    assume().that(graphIsMutable()).isTrue();

    addNode(N1);
    Set<Integer> successors = graph.successors(N1);
    assertThrows(UnsupportedOperationException.class, () -> successors.add(N2));
    putEdge(N1, N2);
    assertThat(graph.successors(N1)).containsExactlyElementsIn(successors);
  }

  @Override
  @Test
  public void incidentEdges_checkReturnedSetMutability() {

    assume().that(graphIsMutable()).isTrue();

    addNode(N1);
    Set<Integer> successors = graph.successors(N1);
    assertThrows(UnsupportedOperationException.class, () -> successors.add(N2));
    putEdge(N1, N2);
    assertThat(graph.successors(N1)).containsExactlyElementsIn(successors);
  }

  @Override
  @Test
  public void incidentEdges_checkReturnedSetMutability() {

    assume().that(graphIsMutable()).isTrue();

    addNode(N1);
    Set<Integer> successors = network.successors(N1);
    assertThrows(UnsupportedOperationException.class, () -> successors.add(N2));
    addEdge(N1, N2, E12);
    assertThat(successors).containsExactlyElementsIn(network.successors(N1));
  }

  @Test
  public void edges_containsOrderMismatch() {
    addEdge(N1, N2, E12);