@ParametricNullness private final R rowKey;
    @ParametricNullness private final C columnKey;
    @ParametricNullness private final V value;

    ImmutableCell(
        @ParametricNullness R rowKey,
        @ParametricNullness C columnKey,
        @ParametricNullness V value) {
      this.rowKey = rowKey;
      this.columnKey = columnKey;
      this.value = value;
    }

   */
  @Override
  public SortedMap<C, V> row(R rowKey) {
    return new TreeRow(rowKey);
  }

  private class TreeRow extends Row implements SortedMap<C, V> {
    @CheckForNull final C lowerBound;
    @CheckForNull final C upperBound;

    TreeRow(R rowKey) {
      this(rowKey, null, null);
    }

    TreeRow(R rowKey, @CheckForNull C lowerBound, @CheckForNull C upperBound) {

    @ParametricNullness private final R rowKey;
    @ParametricNullness private final C columnKey;
    @ParametricNullness private final V value;

    ImmutableCell(
        @ParametricNullness R rowKey,
        @ParametricNullness C columnKey,
        @ParametricNullness V value) {
      this.rowKey = rowKey;
      this.columnKey = columnKey;
      this.value = value;
    }

   */
  @Override
  public SortedMap<C, V> row(R rowKey) {
    return new TreeRow(rowKey);
  }

  private class TreeRow extends Row implements SortedMap<C, V> {
    @CheckForNull final C lowerBound;
    @CheckForNull final C upperBound;

    TreeRow(R rowKey) {
      this(rowKey, null, null);
    }

    TreeRow(R rowKey, @CheckForNull C lowerBound, @CheckForNull C upperBound) {

  /**
   * {@inheritDoc}
   *
   * @throws NullPointerException if {@code rowKey} is {@code null}
   */
  @Override
  public ImmutableMap<C, V> row(R rowKey) {
    checkNotNull(rowKey, "rowKey");
    return MoreObjects.firstNonNull(
        (ImmutableMap<C, V>) rowMap().get(rowKey), ImmutableMap.<C, V>of());
  }

  @Override
  public ImmutableSet<R> rowKeySet() {

   *
   * @throws IllegalArgumentException if {@code rowKey} is not in {@link #rowKeySet()} or {@code
   *     columnKey} is not in {@link #columnKeySet()}.
   */
  @CanIgnoreReturnValue
  @Override
  @CheckForNull
  public V put(R rowKey, C columnKey, @CheckForNull V value) {
    checkNotNull(rowKey);
    checkNotNull(columnKey);
    Integer rowIndex = rowKeyToIndex.get(rowKey);

   *
   * @throws IllegalArgumentException if {@code rowKey} is not in {@link #rowKeySet()} or {@code
   *     columnKey} is not in {@link #columnKeySet()}.
   */
  @CanIgnoreReturnValue
  @Override
  @CheckForNull
  public V put(R rowKey, C columnKey, @CheckForNull V value) {
    checkNotNull(rowKey);
    checkNotNull(columnKey);
    Integer rowIndex = rowKeyToIndex.get(rowKey);

    @Override
    public boolean contains(@CheckForNull Object rowKey, @CheckForNull Object columnKey) {
      synchronized (mutex) {
        return delegate().contains(rowKey, columnKey);
      }
    }

    @Override
    public boolean containsRow(@CheckForNull Object rowKey) {
      synchronized (mutex) {
        return delegate().containsRow(rowKey);
      }
    }

    @Override

    @Override
    public boolean contains(@CheckForNull Object rowKey, @CheckForNull Object columnKey) {
      synchronized (mutex) {
        return delegate().contains(rowKey, columnKey);
      }
    }

    @Override
    public boolean containsRow(@CheckForNull Object rowKey) {
      synchronized (mutex) {
        return delegate().containsRow(rowKey);
      }
    }

    @Override

   * by applying the given {@code AsyncFunction} to the result of the original {@code Future}.
   * Example usage:
   *
   * <pre>{@code
   * ListenableFuture<RowKey> rowKeyFuture = indexService.lookUp(query);
   * ListenableFuture<QueryResult> queryFuture =
   *     transformAsync(rowKeyFuture, dataService::readFuture, executor);
   * }</pre>
   *