code: private void generateSubMenu(final Collection<ActionRef> parents, final ActionRef action, Featurable menu)
      {
          menu.getFeature(Actionable.class).setAction(() ->
          {
              clearMenus();
              createMenus(parents, action.getRefs());
          });
      }
docs: Generate sub menu creation if menu contains sub menu.
  
  @param parents The parents menu.
  @param action The current action.
  @param menu The current menu to check.