public void putValue(String fieldName, @Nullable Object value) {
    _fieldToValueMap.put(fieldName, value);
  }
@Test
  public void testMapValuesEqual() {
    GenericRow first = new GenericRow();
    HashMap<String, Integer> firstData = new HashMap<String, Integer>();
    firstData.put("two", 2);
    first.putValue("one", 1);
    first.putValue("two", firstData);

    GenericRow second = new GenericRow();
    second.putValue("one", 1);
    second.putValue("two", firstData.clone());

    Assert.assertEquals(first, second);
  }