code: @Override
      public Collection<Permission> getAllPermissionsFromPermissionSet(String permissionSet)
          throws PermissionSetNotFoundException {
          Collection<Permission> result = new HashSet<Permission>();
          for (String s : getAllPermissionSetsFromPermissionSet(permissionSet)) {
              result.addAll(getPermissionsFromPermissionSet(s));
          }
          return result;
      }
docs: TODO note: this does not reflect insertion order because HashSet is used