code: @Override
      public RoleSet getRolesForSpecialSubject(String resourceName, String specialSubject) {
          RoleSet roles = null;
          AuthorizationTableService authzTable = featureTables.get(resourceName);
          if (authzTable != null)
              roles = authzTable.getRolesForSpecialSubject(resourceName, specialSubject);
          return roles;
      }
docs: {@inheritDoc}