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help required on multithreading


Joined: Feb 05, 2001
Posts: 16
i have a problem in multithreading which i am using
> > in my code
> > and i am not getting the path out of it.
> >
> > I have designed the servlets for online
> > examination.But the problem is that
> > only one user can give the exam at a time.
> > i have used two variables to trace score and
> > question number.
> > when one user logs in there is no problem.
> >
> > but in between if other one comes,
> > he gets his first question but his score is
> > incremented with the score of first user.
> > similarly his question.
> >
> > if user1 is on fourth question and his score=40;
> > user2 gets score=50 for his first right answer
> > infact it should be 10;
> >
> > i have incremented the score by 10 for each correct
> > answer.
> > the score and question_no are public variables.
> >
> > the test is for 10 questions and i am calling the
> > same servlet in a loop till the completion.
> > it is offcourse not fiesible to design n servlets
> > for n users.
> > i want the same servlet to be used by all the users.
> >
> > what should i do??
> > I am using jdk1.2.2 and Jsdk 2.0
> >
> > please mail me if you can help me.
> > thank you
> > sachin
Rahul Mahindrakar
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Joined: Jul 28, 2000
Posts: 1868
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Rahul Mahindrakar
Ranch Hand

Joined: Jul 28, 2000
Posts: 1868
I guess you have to make use of HttpSessions. This area is adequately addressed in our servlets forum.
I hence move this to the relevant forum.
Peter den Haan
Ranch Hand

Joined: Apr 20, 2000
Posts: 3252
Check out javax.servlet.http.HttpServletRequest.getSession() and javax.servlet.http.HttpSession.setAttribute(String, Object).
Also, never use non-final member or static variables in a servlet unless you know exactly what you're doing. Servlets are multi-threaded! State is generally stored in the request or session objects.
- Peter
I agree. Here's the link:
subject: help required on multithreading
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