code: public PanelUser resolvePanelUser(Panel panel, User user) {
      PanelUserDAO panelUserDAO = new PanelUserDAO();
      PanelUser panelUser = panelUserDAO.findByPanelAndUserAndStamp(panel, user, panel.getCurrentStamp());
      if (panelUser == null) {
        panelUser = panelUserDAO.create(panel, user, panel.getDefaultPanelUserRole(), PanelUserJoinType.ADDED, panel.getCurrentStamp(), user);
      }
      return panelUser;
    }
docs: --------------------------------------------------------------------------------------------------------------------