ImmutableList<Service> copy = ImmutableList.copyOf(services);
    if (copy.isEmpty()) {
      // Having no services causes the manager to behave strangely. Notably, listeners are never
      // fired. To avoid this we substitute a placeholder service.
      logger
          .get()
          .log(
              Level.WARNING,
              "ServiceManager configured with no services.  Is your application configured"