@Override
  public void validate() {
    super.validate();
    sourceOptions.validate();
  }
@Test
  public void testSourceOptionsWithNegativeNumRecords() throws Exception {
    thrown.expect(IllegalArgumentException.class);
    thrown.expectMessage("numRecords should be a non-negative number, but found -100");
    testSourceOptions.numRecords = -100;
    testSourceOptions.validate();
  }