private Set findValuePath()

in mqtt-common/src/main/java/org/apache/rocketmq/mqtt/common/model/Trie.java [170:206]
32 lines of code
10 McCabe index (conditional complexity)

    private Set<String> findValuePath(TrieNode<K, V> currentNode, String[] topicArray, int level, int maxLevel,
                                      StringBuilder builder, boolean isNumberSign) {
        Set<String> result = new HashSet<>();
        // match end of path
        boolean isPathEnd = (level == maxLevel || isNumberSign) && !currentNode.valueSet.isEmpty() && builder.length() > 0;
        if (isPathEnd) {
            result.add(TopicUtils.normalizeTopic(builder.toString().substring(0, builder.length() - 1)));
        }
        // match the '#'
        TrieNode numberMatch = currentNode.children.get(Constants.NUMBER_SIGN);
        if (numberMatch != null) {
            int start = builder.length();
            builder.append(Constants.NUMBER_SIGN).append(Constants.MQTT_TOPIC_DELIMITER);
            result.addAll(findValuePath(numberMatch, topicArray, level + 1, maxLevel, builder, true));
            builder.delete(start, builder.length());
        }
        // match the mqtt-topic path
        if (level < maxLevel && !currentNode.children.isEmpty()) {
            // match the precise
            TrieNode trieNode = currentNode.children.get(topicArray[level]);
            if (trieNode != null) {
                int start = builder.length();
                builder.append(topicArray[level]).append(Constants.MQTT_TOPIC_DELIMITER);
                result.addAll(findValuePath(trieNode, topicArray, level + 1, maxLevel, builder, false));
                builder.delete(start, builder.length());
            }
            // match the '+'
            TrieNode plusMatch = currentNode.children.get(Constants.PLUS_SIGN);
            if (plusMatch != null) {
                int start = builder.length();
                builder.append(Constants.PLUS_SIGN).append(Constants.MQTT_TOPIC_DELIMITER);
                result.addAll(findValuePath(plusMatch, topicArray, level + 1, maxLevel, builder, false));
                builder.delete(start, builder.length());
            }
        }
        return result;
    }