如何在 Java Servlet 中使用 Session？
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How to use Session in Java Servlet?
提问by jl.
I am having issues with session in my java code. Upon submitting a form via post, the java servlet will determine if the captcha is correct. May I know anything that I should add to use the session in java servlet? Is there any thing that I need to import to use session?
我的 java 代码中的会话有问题。通过 post 提交表单后，java servlet 将确定验证码是否正确。我可以知道我应该添加什么以在 java servlet 中使用会话吗？我需要导入任何东西才能使用会话吗？
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
try{
// Validate Captcha
String userCaptcha = request.getParameter("captcha");
Captcha captcha = (Captcha) session.getAttribute(Captcha.NAME);
if (!captcha.isCorrect(userCaptcha)) {
errorMsgs.add("Please input the correct Captcha value.");
}
} catch (RuntimeException e) {
...
}
...
Thank you very much.
非常感谢你。
回答by cletus
Well you'll need:
那么你需要：
// create session if one doesn't exist
HttpSession session = request.getSession(true);
You're not actually referencing a session anywhere in your code.
您实际上并未在代码中的任何位置引用会话。
