code: public boolean addNamedGroupingPolicy(String ptype, String... params) {
          return addNamedGroupingPolicy(ptype, Arrays.asList(params));
      }
docs: addNamedGroupingPolicy adds a named role inheritance rule to the current policy.
  If the rule already exists, the function returns false and the rule will not be added.
  Otherwise the function returns true by adding the new rule.
  
  @param ptype the policy type, can be "g", "g2", "g3", ..
  @param params the "g" policy rule.
  @return succeeds or not.