code: public String getAnnouncementPath(String listenerName)
    {
      return ZKPaths.makePath(
          getListenersPath(),
          Preconditions.checkNotNull(
              StringUtils.emptyToNullNonDruidDataString(listenerName), "Listener name cannot be null"
          )
      );
    }
docs: Build a path for the particular named listener. The first implementation of this is used with zookeeper, but
  there is nothing restricting its use in a more general pathing (example: http endpoint proxy for raft)
  @param listenerName The key for the listener.
  @return A path appropriate for use in zookeeper to discover the listeners with the particular listener name