implements Table<R, C, V> {

  @Override
  public boolean containsRow(@Nullable Object rowKey) {
    return Maps.safeContainsKey(rowMap(), rowKey);
  }

  @Override
  public boolean containsColumn(@Nullable Object columnKey) {
    return Maps.safeContainsKey(columnMap(), columnKey);
  }

  @Override
  public Set<R> rowKeySet() {
    return rowMap().keySet();
  }

  @Override

      return new AsMapEntries();
    }

    // The following methods are included for performance.

    @Override
    public boolean containsKey(@Nullable Object key) {
      return Maps.safeContainsKey(submap, key);
    }

    @Override
    public @Nullable Collection<V> get(@Nullable Object key) {
      Collection<V> collection = safeGet(submap, key);
      if (collection == null) {

      return null;
    }
  }

  /**
   * Delegates to {@link Map#containsKey}. Returns {@code false} on {@code ClassCastException} and
   * {@code NullPointerException}.
   */
  static boolean safeContainsKey(Map<?, ?> map, @Nullable Object key) {
    checkNotNull(map);
    try {
      return map.containsKey(key);
    } catch (ClassCastException | NullPointerException e) {
      return false;
    }
  }