columnBuilder.put(col.getKey(), ImmutableMap.copyOf(col.getValue()));
    }
    this.columnMap = columnBuilder.buildOrThrow();
  }

  @Override
  public ImmutableMap<C, Map<R, V>> columnMap() {
    // Casts without copying.
    return ImmutableMap.copyOf(columnMap);
  }

  @Override
  public ImmutableMap<R, Map<C, V>> rowMap() {
    // Casts without copying.

      cellColumnIndices[i] = columnIndex;
    }
    this.cellRowIndices = cellRowIndices;
    this.cellColumnIndices = cellColumnIndices;
    this.rowMap = new RowMap();
    this.columnMap = new ColumnMap();
  }

  /** An immutable map implementation backed by an indexed nullable array. */
  private abstract static class ImmutableArrayMap<K, V> extends IteratorBasedImmutableMap<K, V> {
    private final int size;

    public Set<C> columnKeySet() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.columnKeySet();
    }

    @Override
    public Map<C, Map<R, V>> columnMap() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.columnMap();
    }

    @Override
    public boolean contains(Object rowKey, Object columnKey) {
      assertTrue(Thread.holdsLock(mutex));

      columnBuilder.put(col.getKey(), ImmutableMap.copyOf(col.getValue()));
    }
    this.columnMap = columnBuilder.buildOrThrow();
  }

  @Override
  public ImmutableMap<C, Map<R, V>> columnMap() {
    // Casts without copying.
    return ImmutableMap.copyOf(columnMap);
  }

  @Override
  public ImmutableMap<R, Map<C, V>> rowMap() {
    // Casts without copying.

  }

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

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

  @Override
  public Set<C> columnKeySet() {
    return columnMap().keySet();
  }

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

  }

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

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

  @Override
  public Set<C> columnKeySet() {
    return columnMap().keySet();
  }

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

    RowSortedTable<Integer, String, Character> table = TreeBasedTable.create();
    table.put(1, "foo", 'a');
    table.put(1, "bar", 'b');
    table.put(3, "foo", 'c');
    return unmodifiableRowSortedTable(table).columnMap();
  }

    Table<Integer, String, Character> table = HashBasedTable.create();
    table.put(1, "foo", 'a');
    table.put(1, "bar", 'b');
    table.put(3, "foo", 'c');
    return unmodifiableTable(table).columnMap();
  }

    original.put(1, "foo", 'a');
    assertSame(original.columnKeySet(), transpose.rowKeySet());
    assertSame(original.rowKeySet(), transpose.columnKeySet());
    assertSame(original.columnMap(), transpose.rowMap());
    assertSame(original.rowMap(), transpose.columnMap());
    assertSame(original.values(), transpose.values());
    assertEquals(original.row(1), transpose.column(1));
    assertEquals(original.row(2), transpose.column(2));

  }

  public void testColumnKeySet() {
    assertEquals(ImmutableSet.of(), INSTANCE.columnKeySet());
  }

  public void testColumnMap() {
    assertEquals(ImmutableMap.of(), INSTANCE.columnMap());
  }

  public void testContains() {
    assertFalse(INSTANCE.contains('a', 1));
  }

  public void testContainsColumn() {
    assertFalse(INSTANCE.containsColumn(1));
  }