private Set<String> getMatchingSubscriptions(String partition, String topic) {
Set<String> topicFilterKeys = new HashSet<>();
ListIterator<String> pathIterator =
Arrays.asList(topic.split(Constant.PATH_SEPARATOR)).listIterator();
List<String> growingTitles = new ArrayList<>();
while (pathIterator.hasNext()) {
String name = pathIterator.next();
List<String> slWildCardList = new ArrayList<>(growingTitles);
if (pathIterator.hasNext()) {
// We deal with wildcard.
slWildCardList.add(Constant.SINGLE_LEVEL_WILDCARD);
topicFilterKeys.add(quickCheckIdKey(partition, slWildCardList));
} else {
// we deal with full topic
slWildCardList.add(name);
}
List<String> reverseSlWildCardList = new ArrayList<>(slWildCardList);
growingTitles.add(name);
int sizeOfTopic = slWildCardList.size();
if (sizeOfTopic > 1) {
sizeOfTopic -= 1;
for (int i = 0; i < sizeOfTopic; i++) {
if (i >= 0) {
slWildCardList.set(i, Constant.MULTI_LEVEL_WILDCARD);
reverseSlWildCardList.set(sizeOfTopic - i, Constant.MULTI_LEVEL_WILDCARD);
topicFilterKeys.add(quickCheckIdKey(partition, slWildCardList));
topicFilterKeys.add(quickCheckIdKey(partition, reverseSlWildCardList));
}
}
}
}
topicFilterKeys.add(quickCheckIdKey(partition, growingTitles));
return topicFilterKeys;
}
