*
   * <p>In contrast, the maps returned by {@code rowMap().get()} have the same behavior as those
   * returned by {@link #row}. Those maps may support {@code setValue()}, {@code put()}, and {@code
   * putAll()}.
   *
   * @return a map view from each row key to a secondary map from column keys to values
   */
  Map<R, Map<C, V>> rowMap();

  /**

   *
   * <p>In contrast, the maps returned by {@code rowMap().get()} have the same behavior as those
   * returned by {@link #row}. Those maps may support {@code setValue()}, {@code put()}, and {@code
   * putAll()}.
   *
   * @return a map view from each row key to a secondary map from column keys to values
   */
  Map<R, Map<C, V>> rowMap();

  /**

    @Override
    protected Map<String, Map<Integer, Character>> makePopulatedMap() {
      Table<String, Integer, Character> table = makeTable();
      populateTable(table);
      return table.rowMap();
    }

    // `protected` to work around b/320650932 / KT-67447 runtime crash
    protected final void populateTable(Table<String, Integer, Character> table) {
      table.put("foo", 1, 'a');

    @Override
    protected Map<String, Map<Integer, Character>> makePopulatedMap() {
      Table<String, Integer, Character> table = makeTable();
      populateTable(table);
      return table.rowMap();
    }

    // `protected` to work around b/320650932 / KT-67447 runtime crash
    protected final void populateTable(Table<String, Integer, Character> table) {
      table.put("foo", 1, 'a');

      synchronized (mutex) {
        return collection(delegate().values(), mutex);
      }
    }

    @Override
    public Map<R, Map<C, V>> rowMap() {
      synchronized (mutex) {
        return map(transformValues(delegate().rowMap(), m -> map(m, mutex)), mutex);
      }
    }

    @Override
    public Map<C, Map<R, V>> columnMap() {
      synchronized (mutex) {

  }

  public void testRowMapComparator() {
    sortedTable = TreeBasedTable.create();
    assertThat(sortedTable.rowMap().comparator()).isEqualTo(Ordering.natural());

    sortedTable = TreeBasedTable.create(Collections.reverseOrder(), Ordering.usingToString());
    assertThat(sortedTable.rowMap().comparator()).isEqualTo(Collections.reverseOrder());
  }

  public void testRowMapFirstKey() {

      synchronized (mutex) {
        return collection(delegate().values(), mutex);
      }
    }

    @Override
    public Map<R, Map<C, V>> rowMap() {
      synchronized (mutex) {
        return map(transformValues(delegate().rowMap(), m -> map(m, mutex)), mutex);
      }
    }

    @Override
    public Map<C, Map<R, V>> columnMap() {
      synchronized (mutex) {

    assertThat(transpose.columnKeySet()).isSameInstanceAs(original.rowKeySet());
    assertThat(transpose.rowMap()).isSameInstanceAs(original.columnMap());
    assertThat(transpose.columnMap()).isSameInstanceAs(original.rowMap());
    assertThat(transpose.values()).isSameInstanceAs(original.values());
    assertEquals(original.row(1), transpose.column(1));

    }
  }

  public final void testConsistentToString() {
    for (ImmutableTable<Character, Integer, String> testInstance : getTestInstances()) {
      assertThat(testInstance.toString()).isEqualTo(testInstance.rowMap().toString());
    }
  }

  public final void testConsistentHashCode() {
    for (ImmutableTable<Character, Integer, String> testInstance : getTestInstances()) {

  }

  public void testRowKeySet() {
    assertEquals(ImmutableSet.of(), INSTANCE.rowKeySet());
  }

  public void testRowMap() {
    assertEquals(ImmutableMap.of(), INSTANCE.rowMap());
  }

  public void testValues() {
    assertTrue(INSTANCE.values().isEmpty());
  }