問題描述

我正在開發(fā)基于 geo-location 呈現(xiàn)內容的 servlet 頁面，我想同時使用 sendRedirect 和 forward;例如;您從 France 瀏覽 example.com/aPage.jsp；首先，我希望 servlet 將您重定向到 example.com/fr/aPage.jsp，然后將您轉發(fā)到 resources 頁面.

I'm working on servlet page that renders content based on geo-location, and I want to use both sendRedirect and forward together; e.g; you browse example.com/aPage.jsp from France; first I want the servlet to redirect you to example.com/fr/aPage.jsp and then forward you to the resources page.

這就是我的 servlet 中的內容:

This is what I have in my servlet:

public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  ....
  response.sendRedirect(REDIRECT_URL_BASED_ON_GEO);
  // after redirect forward the resources page
  RequestDispatcher view = request.getRequestDispatcher(RESOURCES_PAGE);
  view.forward(request, response);
  ...
}

但我明白了:

java.lang.IllegalStateException: Cannot forward after response has been committed

我知道錯誤出現(xiàn)是因為我不能同時使用 sendRedirect 和 forward 一個又一個，但我不知道如何在沒有這個的情況下實現(xiàn)我想要的(如上所述).

I know the error appears because I can't use both sendRedirect and forward one after another, but I don't know how to achieve what I want (as described above) without this.

有什么幫助嗎?

推薦答案

 response.sendRedirect(REDIRECT_URL_BASED_ON_GEO);
  // after redirect forward the resources page

在那一行之后，您的回復開始寫入 clinet.

After that line , Your response start writing to clinet.

您正在嘗試向其中添加其他數(shù)據(jù).

And you are trying to add additional data to it.

服務器已經(jīng)完成響應頭的寫入，并且正在寫入內容的正文，以及您嘗試在標題中寫入更多內容的點 - 當然它不能倒帶.

The server has already finished writing the response header and is writing the body of the content, and which point you are trying to write more to the header - of course it cant rewind.

所以，處理 servlet 時的拇指規(guī)則是

So,Thumb rule while dealing with servlet is

在redirect或forward添加return語句之前完成你的邏輯.所以執(zhí)行到此結束.

Finish your logic before redirect or forward add return statement.So execution ends there .

這篇關于Servlet:提交響應后無法轉發(fā)的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網(wǎng)！