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无法获取javaweb响应setAttribute_Java_Servlets_Jakarta Ee - Fatal编程技术网

无法获取javaweb响应setAttribute

无法获取javaweb响应setAttribute,java,servlets,jakarta-ee,Java,Servlets,Jakarta Ee,我是初学者。我想在servlet上练习。在同一个servlet中,我不知道为什么我不能获得attritube,在forward之后,我也不能获得属性 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=utf-8");

我是初学者。我想在servlet上练习。在同一个servlet中,我不知道为什么我不能获得attritube,在
forward
之后,我也不能获得属性

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    response.setContentType("text/html;charset=utf-8");
    request.setAttribute("aa","asd");
    System.out.println(request.getAttribute("aa"));
    RequestDispatcher requestDispatcher = request.getRequestDispatcher("/WEB-INF/classes/ResultServlet");
    requestDispatcher.forward(request,response);
}
在servlet上打印时需要使用以下命令

PrintWriter out = response.getWriter();
out.print(request.getAttribute("aa"));
getRequestDispatcher()
中,您需要提供资源的url。您已经传递了servlet的类文件路径。
WEB-INF下的文件不能直接访问。
将servlet文件和一些包放在
src
文件夹下。并且只传递servlet名称

PrintWriter out = response.getWriter();
out.print(request.getAttribute("aa"));