@SuppressWarnings("MethodDoesntCallSuperMethod")
  @Override
  public DataSchema clone() {
    return new DataSchema(_columnNames.clone(), _columnDataTypes.clone());
  }
@Test
  public void testClone() {
    DataSchema dataSchema = new DataSchema(COLUMN_NAMES, COLUMN_DATA_TYPES);
    DataSchema dataSchemaClone = dataSchema.clone();
    Assert.assertEquals(dataSchema, dataSchemaClone);
    Assert.assertEquals(dataSchema.hashCode(), dataSchemaClone.hashCode());
  }