code: public void dropRole(String name) {
  
          if (!isRole(name)) {
              throw Error.error(ErrorCode.X_0P000, name);
          }
  
          if (GranteeManager.isReserved(name)) {
              throw Error.error(ErrorCode.X_42507);
          }
  
          removeGrantee(name);
      }
docs: Attempts to drop a Role with the specified name
  from this object's set. <p>
  
  A successful drop action consists of: <p>
  
  <UL>
  
  <LI>removing the Grantee object with the specified name
  from the set.
  </UL> <p>