code: synchronized List<HandlerHolder> findHandlers(String topic) {
          List<HandlerHolder> handlers = new ArrayList<HandlerHolder>();
  
          List<HandlerHolder> discreteHandlers = discreteEventHandlers.get(topic);
          if (discreteHandlers != null) {
              handlers.addAll(discreteHandlers);
          }
  
          for (Map.Entry<String, List<HandlerHolder>> entry : wildcardEventHandlers.entrySet()) {
              if (topic.startsWith(entry.getKey())) {
                  handlers.addAll(entry.getValue());
              }
          }
  
          return handlers;
      }
docs: Find all registered <code>EventHandler</code> references that have
  expressed interest in the specified topic.
  
  @param topic
  the topic associated with the event to publish
  @return the (possibly empty) list of handlers interested in the topic