code: public User createUser(HsqlName name,
                             String password) {
  
          // This will throw an appropriate exception if grantee already exists,
          // regardless of whether the name is in any User, Role, etc. list.
          User user = granteeManager.addUser(name);
  
          user.setPassword(password);
  
          boolean success = userList.add(name.name, user);
  
          if (!success) {
              throw Error.error(ErrorCode.X_28503, name.statementName);
          }
  
          return user;
      }
docs: Creates a new User object under management of this object. <p>
  
  A set of constraints regarding user creation is imposed: <p>
  
  <OL>
  <LI>If the specified name is null, then an
  ASSERTION_FAILED exception is thrown stating that
  the name is null.
  
  <LI>If this object's collection already contains an element whose
  name attribute equals the name argument, then
  a GRANTEE_ALREADY_EXISTS exception is thrown.
  (This will catch attempts to create Reserved grantee names).
  </OL>