code: public User loadUser (String authcode)
          throws PersistenceException
      {
          User user = (authcode == null) ? null : _repository.loadUserBySession(authcode);
          if (USERMGR_DEBUG) {
              log.info("Loaded user by authcode", "code", authcode, "user", user);
          }
          return user;
      }
docs: Loads up a user based on the supplied session authentication token.