*   <dd>{@code 00 00 00 00 00 00 00 00 00 00 00 00 c0 a8 00 01}
 *   <dt>An IPv6 "IPv4 mapped" address, {@code "::ffff:192.168.0.1"}.
 *   <dd>{@code 00 00 00 00 00 00 00 00 00 00 ff ff c0 a8 00 01}
 * </dl>
 *
 * <p>A few notes about IPv6 "IPv4 mapped" addresses and their observed use in Java.
 *
 * <p>"IPv4 mapped" addresses were originally a representation of IPv4 addresses for use on an IPv6

 * with the range (if any) that contains a specified key.
 *
 * <p>In contrast to {@link RangeSet}, no "coalescing" is done of {@linkplain
 * Range#isConnected(Range) connected} ranges, even if they are mapped to the same value.
 *
 * @author Louis Wasserman
 * @since 14.0
 */
@SuppressWarnings("rawtypes") // https://github.com/google/guava/issues/989
@DoNotMock("Use ImmutableRangeMap or TreeRangeMap")
@GwtIncompatible

  }

  /**
   * Returns a {@code Collector} that accumulates elements into an {@code ImmutableTable}. Each
   * input element is mapped to one cell in the returned table, with the rows, columns, and values
   * generated by applying the specified functions. If multiple inputs are mapped to the same row
   * and column pair, they will be combined with the specified merging function in encounter order.
   *

     */
    <T> void set(@Nonnull Key<T> key, @Nullable T value);

    /**
     * Associates the specified session data with the given key if the key is currently mapped to the given value. This
     * method provides an atomic compare-and-update of some key's value.
     *
     * @param key the key under which to store the session data, must not be {@code null}

    for (Entry<K, V> entry : entries) {
      assertFalse("Should not contain entry " + entry, actualContents().contains(entry));
      assertFalse(
          "Should not contain key " + entry.getKey() + " mapped to value " + entry.getValue(),
          equal(getMap().get(entry.getKey()), entry.getValue()));
    }
  }

  private static boolean equal(@Nullable Object a, @Nullable Object b) {

                getKeyForNullValue(),
                v3(),
                (oldV, newV) -> {
                  throw new AssertionFailedError(
                      "Should not call merge function if key was mapped to null");
                }));
    expectReplacement(entry(getKeyForNullValue(), v3()));
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_KEYS})
  public void testMergeAbsentNullKey() {
    assertEquals(

  }

  /**
   * Returns a {@code Collector} that accumulates elements into an {@code ImmutableTable}. Each
   * input element is mapped to one cell in the returned table, with the rows, columns, and values
   * generated by applying the specified functions. If multiple inputs are mapped to the same row
   * and column pair, they will be combined with the specified merging function in encounter order.
   *

    for (Entry<K, V> entry : entries) {
      assertFalse("Should not contain entry " + entry, actualContents().contains(entry));
      assertFalse(
          "Should not contain key " + entry.getKey() + " mapped to value " + entry.getValue(),
          equal(getMap().get(entry.getKey()), entry.getValue()));
    }
  }

  private static boolean equal(@Nullable Object a, @Nullable Object b) {

   * the result of applying {@code countFunction} to the inputs.
   *
   * <p>If the mapped elements contain duplicates (according to {@link Object#equals}), the first
   * occurrence in encounter order appears in the resulting multiset, with count equal to the sum of
   * the outputs of {@code countFunction.applyAsInt(t)} for each {@code t} mapped to that element.
   *
   * @since 22.0
   */
  public static <T extends @Nullable Object, E>

  /**
   * All node connections in this graph, in edge insertion order.
   *
   * <p>Note: This field and {@link #adjacentNodeValues} cannot be combined into a single
   * LinkedHashMap because one target node may be mapped to both a predecessor and a successor. A
   * LinkedHashMap combines two such edges into a single node-value pair, even though the edges may
   * not have been inserted consecutively.
   */