Hi,
I donno if it works.. just check it..... Have a regular check with
res.isCommited() .... if it returns true... kill the thread...
other wise it means u should give a server push in regular interval....
Arun.N
----- Original Message -----
From: Sudarson_Pratihar <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Monday, April 30, 2001 10:44 AM
Subject: Re: [SERVLET-INTEREST] How to detect browser stop -- it is
possible!
> > ----------
> > From: Sudarson_Pratihar
> > Sent: Monday, April 30, 2001 10:39 AM
> > To: 'A mailing list for discussion about Sun Microsystem's Java
Servlet
> > API Technology.'
> > Subject: RE: How to detect browser stop -- it is possible!
> >
> > yeah, 'm using the server push technique as it is used in pushlet, but
> > messaging portion I 'm managing thru JMS not thru their framework. That
is
> > when have the problem of servlet instances alive when browser is
stopped.
> >
> > ----------
> > From: Tarun Ramakrishna Elankath[SMTP:[EMAIL PROTECTED]]
> > Reply To: A mailing list for discussion about Sun Microsystem's Java
> > Servlet API Technology.
> > Sent: Monday, April 30, 2001 8:45 AM
> > To: [EMAIL PROTECTED]
> > Subject: Re: How to detect browser stop -- it is possible!
> >
> > I think you have only two options in this kind of situation :
> >
> > 1) Let the browser contain an applet that communicates with the server.
> > The
> > applet unlike the browser window is outside the "purview" of the stop
> > button
> > of the browser.The applet can
> > a) open a new frame (AWT) that displays the information that the
> > server
> > has pushed
> > b) Using LiveConnect, the applet opens a new browser window (through
> > javascript) and writes to that window (only possible in Netscape)
> >
> > 2) Send events from servlets to DHTML client browsers :
> > see JavaWorld article
> > http://www.javaworld.com/javaworld/jw-03-2000/jw-03-pushlet.html
> > ----- Original Message -----
> > From: "Sudarson_Pratihar" <[EMAIL PROTECTED]>
> > To: <[EMAIL PROTECTED]>
> > Sent: Sunday, April 29, 2001 5:14 PM
> > Subject: Re: How to detect browser stop -- it is possible!
> >
> >
> > > Hi,
> > >
> > > Really thanks for taking interest.
> > >
> > > What my intension is that I want to develop a servlet based
application
> > > which will update the browser view as and when the system get some
input
> > > data comes to the server(may be coming to the server thru real time
> > input).
> > >
> > > For that, I'm using JMS and in the serverlet , I'm not clsoing the
> > socket
> > > i.e. servelet is waiting for the message. When some JMS message comes
to
> > the
> > > servlet, the browser view is updated thru server push mechanism.
> > >
> > > But the problem is that when a browser stop button being pressed
leaves
> > the
> > > listener object still alive and that is of major concern.
> > >
> > > This is the senario. I have also doing experiment with IOException
> > raised
> > by
> > > the servletoutputstream.flush(). But still wanting more effective
> > solution.
> > >
> > > Thanks and Regards,
> > > Sudarson
> > >
> > > > ----------
> > > > From: Tarun Ramakrishna Elankath[SMTP:[EMAIL PROTECTED]]
> > > > Reply To: A mailing list for discussion about Sun Microsystem's
> > Java
> > > > Servlet API Technology.
> > > > Sent: Saturday, April 28, 2001 8:43 PM
> > > > To: [EMAIL PROTECTED]
> > > > Subject: Re: How to detect browser stop -- it is possible!
> > > >
> > > > Hmm... (brain ticking)
> > > > When you press the stop button on a browser, chances are that
the
> > > > browser has already send a request to a server and is waiting for a
> > > > response. Ofcourse you could also have pressed the stop button when
> > the
> > > > browser is still issuing a request, but the time required for
issuing
> > a
> > > > request is much greater than the time required for waiting for the
> > > > response.
> > > > (unless you have some huge POST data) .
> > > > So the maximum that you could hope for is that the servlet
throws
> > an
> > > > IOException when writing to the output stream. And then hope that
the
> > > > exception was thrown because the client clicked the stop button.
This
> > is
> > > > loony logic because this IOException could be thrown for other
reasons
> > as
> > > > well, such as the connection getting lost or timed out.
> > > > I really dont believe that you could detect the stop button
being
> > > > clicked. There is no event handler in JavaScript that detects the
stop
> > > > button being clicked. (for very good reasons : - which is the script
> > that
> > > > should detect it ? the one that got unloaded or the one that is
> > loading
> > ?)
> > > > You could get around this with some convoluted Javascript hacks
> > that
> > I
> > > > do not recommend. One such tactic is
> > > > that you could open a window with no stop buttons at all (and
disable
> > the
> > > > hot keys) so that the only way the user can stop the page from
loading
> > is
> > > > to
> > > > close the window.
> > > > Another would be to have a hidden frameset in each page (width &
> > > > height
> > > > =0) which has a script that monitors the activity of the links in
the
> > > > visible frameset, and checks that the link that was clicked on was
> > loaded.
> > > > This solution is more in the realm of DHTML than servlets and doesnt
> > serve
> > > > much purpose apart from making simple things complicated.
> > > > About the cleaning up work, it depends on what volume of data
you
> > > > happen
> > > > to have associated for each user session. You can either set timeout
> > > > intervals for sessions or if you are reasonably sure that the client
> > has
> > > > terminated his/her session, you could manually get rid of the data
> > > > yourself.
> > > > You cannot "destroy" objects that are created within the
servlets.
> > At
> > > > maximum, you can set their references to null and hope that the
> > garbage
> > > > collector collects them. If you are planning to destroy instance
> > objects,
> > > > then thats dangerous, because an instance of a servlet could be
> > assigned
> > > > multiple requests in different threads (unless you are using the
> > > > SingleThreadedModel)
> > > > I am actually quite confused as to what are you trying to do.
> > Could
> > > > you
> > > > give a brief explanation of what are you trying to achieve ? Maybe
we
> > can
> > > > accomplish it another way.
> > > >
> > > > ----- Original Message -----
> > > > From: "Sudarson_Pratihar" <[EMAIL PROTECTED]>
> > > > To: <[EMAIL PROTECTED]>
> > > > Sent: Saturday, April 28, 2001 3:42 PM
> > > > Subject: Re: How to detect browser stop -- it is possible!
> > > >
> > > >
> > > > > Thanks for the reply. But what you have talked about the Browser
> > closing
> > > > ,
> > > > > I'm talking about the stop button(or interrupt) button of browser.
> > > > > Is that applicable for that also?
> > > > >
> > > > > And if so, how can I destroy the objects that are created within
the
> > > > > particular servlet.
> > > > >
> > > > > Pls highlight on the clean up work.
> > > > >
> > > > > Regards,
> > > > > Sudarson
> > > > >
> > > > >
> > > > > > ----------
> > > > > > From: Tarun Ramakrishna
Elankath[SMTP:[EMAIL PROTECTED]]
> > > > > > Reply To: A mailing list for discussion about Sun
> > Microsystem's
> > > > Java
> > > > > > Servlet API Technology.
> > > > > > Sent: Friday, April 27, 2001 8:36 PM
> > > > > > To: [EMAIL PROTECTED]
> > > > > > Subject: Re: How to detect browser stop -- it is possible!
> > > > > >
> > > > > > Well IT IS actually possible for the browser to inform the
server
> > that
> > > > it
> > > > > > has been closed.! You would have to do the scripting via
> > JavaScript
> > > > > > though.
> > > > > > You could set a onunload() event handler for the window. This
> > onunload
> > > > > > event
> > > > > > handler could then call a server-side script with the parameter
> > > > > > close=true.
> > > > > > The server-side script could then use this information to
perform
> > > > > > some-clean
> > > > > > up operations. However the sever-side script SHOULD NOT write to
> > the
> > > > > > client,
> > > > > > because by that time IE/NS would have closed the window down.
> > > > > >
> > > > > > A rough outline of how this works is like follows :
> > > > > >
> > > > > > <script language="javascript">
> > > > > > window.onunload = function() {
> > > > > > location.href="detect_close.jsp?close=true";
> > > > > > }
> > > > > > </script>
> > > > > >
> > > > > > You could do whatever you want in the JSP. Note that the JSP
WILL
> > KNOW
> > > > > > which
> > > > > > client has shut the window, because the browser would send the
> > > > > > session/cookie data in the request just before the window shuts
> > down.
> >
> >
> >
>
>
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