table.put("z", 1, 'a');
    return table;
  }

  @Override
  protected Map<String, Map<Integer, Character>> makePopulatedMap() {
    TreeBasedTable<String, Integer, Character> table = makeTable();
    populateTable(table);
    return table.rowMap().subMap("b", "x");
  }

  @Override
  protected Map<String, Map<Integer, Character>> makeEmptyMap() {
    return makeTable().rowMap().subMap("b", "x");
  }

  @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');
      table.put("bar", 1, 'b');