void initializeSubscription() {
        if (usesPatternSubscription()) {
            log.debug("Found pattern subscribed source topics, initializing consumer's subscription pattern.");
            sourceTopicPatternString = buildSourceTopicsPatternString();
        } else {
            log.debug("No source topics using pattern subscription found, initializing consumer's subscription collection.");
            fullSourceTopicNames = maybeDecorateInternalSourceTopics(rawSourceTopicNames);
            Collections.sort(fullSourceTopicNames);
        }
    }
@return  the full names (including application id/topology name prefix) of all source topics whose
         processors are connected to the given state store
streams/src/main/java/org/apache/kafka/streams/processor/internals/InternalTopologyBuilder.java