@Override
	protected String toDSL() {
		return String.format("kafka --zkconnect=%s --topic=%s  --outputType=%s", zkConnect, topic, outputType);
	}
Returns an instance of the KafkaSource using defaults.

@return instance of the KafkaSource
spring-xd-test-fixtures/src/main/java/org/springframework/xd/test/fixtures/KafkaSource.java