try {
UserRegistry userRegistry =
this.registryService.getGovernanceSystemRegistry(EventBrokerHolder.getInstance().getTenantId());
if (!userRegistry.resourceExists(topicStoragePath)) {
userRegistry.put(topicStoragePath,
userRegistry.newCollection());
}
Resource root = userRegistry.get(this.topicStoragePath);
TopicNode rootTopic = new TopicNode("/", "/");
buildTopicTree(rootTopic, (Collection) root, userRegistry);
return rootTopic;