@Override
        public TopicNameExtractor<K, V> topicNameExtractor() {
            if (topicNameExtractor instanceof StaticTopicNameExtractor) {
                return null;
            } else {
                return topicNameExtractor;
            }
        }
@return names of all source topics, including the application id/named topology prefix for repartition sources
streams/src/main/java/org/apache/kafka/streams/processor/internals/InternalTopologyBuilder.java