@Test
public void testDefaultSettingsOnReConfigure() throws Exception {

  String sampleConsumerProp = "auto.offset.reset";
  String sampleConsumerVal = "earliest";
  String group = "group";
  Context context = prepareDefaultContext(group);
  context.put(KafkaSourceConstants.KAFKA_CONSUMER_PREFIX + sampleConsumerProp,
      sampleConsumerVal);
  context.put(TOPIC, "random-topic");
  kafkaSource.configure(context);
  Assert.assertEquals(sampleConsumerVal,
      kafkaSource.getConsumerProps().getProperty(sampleConsumerProp));
  context = prepareDefaultContext(group);
  context.put(TOPIC, "random-topic");
  kafkaSource.configure(context);
  Assert.assertNull(kafkaSource.getConsumerProps().getProperty(sampleConsumerProp));
}