javax.persistence.PersistenceException：java.lang.IllegalStateException：此Web容器尚未启动

Question

我有这个servlet：

@WebServlet("/admin/list_users")
public class ListUsersService extends HttpServlet {

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        UserService userServices = new UserService();
        List<Users> listUsers = userServices.listUser();
        request.setAttribute("listUsers", listUsers);

        String listPage = "user_list.jsp";
        RequestDispatcher requestDispatcher = request.getRequestDispatcher(listPage);
        requestDispatcher.forward(request, response);
    }
}

在IntelliJ + GlassFish中执行userServices.listUser()时，它将抛出：

javax.persistence.PersistenceException：java.lang.IllegalStateException：此Web容器尚未启动

相同的代码在Eclipse + Tomcat中可以完美地工作。

我的错误是什么？谢谢！