DataCell { @Override public String toString() { return row.getStringValue(columnName); } DataCell(final DataRow row, final String columnName); static DataCell createDataCell(final DataRow row, final String col); @Override String toString(); boolean equalTo(final DataCell cell2);  }
@Test public void toStringShouldInvokeDataRowGetStringValue() { cell.toString(); verify(row).getStringValue("n"); }