private @NotNull List<TreeStructureProvider> getProvidersDumbAware() {
    if (myProject == null) {
      return Collections.emptyList();
    }

    final List<TreeStructureProvider> providers = getProviders();
    if (providers == null) {
      return Collections.emptyList();
    }

    return DumbService.getInstance(myProject).filterByDumbAwareness(providers);
  }
private @NotNull List<TreeStructureProvider> getProvidersDumbAware()