I had writen a servlet who generates a dynamic PDF document with a long
elaboration time (some minutes).
In the mean time the client browser that had made the servlet request,
shows the errors "HTTP 500 - Internal server error" or "Unable to find
the server or DNS error".
The servlet elaboration continue without exception and produces the
document ... but the result never arrives to the client.
Someone knows more about this problem?
There are some HTTP tricks to keep the browser from
getting a timeout. Multipart MIME may work, spawn
the PDF generator off as Java thread, push some
HTML saying "Please Wait" and a space every odd second
(flush the stream), and push the PDF as the second part.
(maybe this helps:
Another possibility is to use automatic refresh, again
spawn the PDF generator, push a "Please Wait" HTML, if
the PDF is requested again check whether there is the
generator thread, if it's still working push the HTML
again, otherwise send the PDF.