如何更改HttpServlet Request.servletpath?

我使用了几个JSP页面和一个servlet。

Servlet doPost():

String userPath = request.getServletPath();
if (userPath.equals("/PageAdm")) {
     String username = request.getParameter("username");
     String password = request.getParameter("password");
     User userone = new User(username, password);
     request.setAttribute("user", user);
     RequestDispatcher view = request.getRequestDispatcher("view/Page.jsp");
     view.forward(request, response);
} else if (userPath.equals("/Page")) {
     String username = request.getParameter("username");
     UsersService us = new UsersService();
     User user = us.getUserByUsername(username);
     request.setAttribute("user", user);
     RequestDispatcher view = request.getRequestDispatcher("view/UserNameEdit.jsp");
     view.forward(request, response);
}

登录时,我可以更改用户名,但当我提交表单(单击)进行更改时,servlet路径仍然是“/PageAdm”,但必须是“/Page”,这样我才能更改用户名。如何更改servlet路径,使其进入“/UserNameEdit”?