> -----Original Message----- > From: Rizwan Merchant [mailto:[EMAIL PROTECTED] > Sent: Friday, July 16, 2004 4:06 PM > To: 'Struts Users Mailing List' > Subject: RE: Intermediate loading page > > > > Hi Craig, > > Thanks for the reply. I came across this solution, but does > this not mean > that the user will only be able to generate one report at a > time (since we > are storing the flag in the user's session)? If the user > starts generating a > second report which is much smaller than the first then would this not > create a problem?
If you use the same session variable as a flag, then yes.. but you could use the same session variable as a "char of your choice" delimited string, where the values indicate the report name being generated. Or, if you like easy.... a different session var for each report. > > Thanks again for your input. Much appreciated. > > -Riz. > > -----Original Message----- > From: Craig McClanahan [mailto:[EMAIL PROTECTED] > Sent: Friday, July 16, 2004 3:37 PM > To: Struts Users Mailing List > Subject: Re: Intermediate loading page > > Rizwan Merchant wrote: > > > > > > > I am working on a web application using the Struts > framework. Using a > > form on a jsp page, I generate a report which is displayed > in pdf on a > > new screen. The report is generated through an Action class > method. I > > would like to display a "Please wait" screen while the > report is being > > generated. > > > > The action class method calls functions that generate a pdf > file and > > then redirects control to that file. So I cannot use the flush() > > method to send html to the browser while the report is > being generated > > (once a response is committed it cannot be written to > again). Neither > > can I use the 'div' tag method as my new page is not a jsp > page (it is > > a new browser window with pdf file displayed inside it). > > One common strategy for this sort of thing is to refactor > your action into > several, along the following lines: > > * The Action that is currently creating the PDF should instead > fire off a background thread to do the report preparation. It > will then forward to a "Please Wait" page (see below). > > * The background thread should do whatever is needed to prepare > the PDF file, and set a flag variable in the user's session > when it's > done, > followed by terminating the thread. > > * The "Please Wait" page should say something like "Report generation > in progress", and use a meta-refresh tag to automatically > submit itself > every few seconds, with the destination being a "Done Yet" action. > > * The "Done Yet" action will consult the flag variable in the user's > session. > If its not there, forward back to the "Please Wait" page > again. If it's > done, forward to the URL to retrieve the PDF itself. > > Craig > > > > > > My code is shown below.... > > > > //the jsp code calling the action > > <nested:form action="/reports.do?action=getTransactionReports" > > target="_blank"> > > > > > > // The Action class > > public ActionForward getTransactionReports(ActionMapping mapping, > > ActionForm form, HttpServletRequest request, HttpServletResponse > > response) throws Exception { > > > > ICustomerAdministrationClient admin_impl = > > getCustomerAdministrationService(request); > > > > //enforce user permission > > enforceFeaturePermissions(EMSConstants.FEATURE_REPORTS, request, 1); > > > > EMSBaseAdminForm admin_form = (EMSBaseAdminForm)form; ReportsForm > > reportsForm = admin_form.getReportsForm(); > > > > //cant do this as it creates an IllegalStateException // > PrintWriter > > html = response.getWriter(); // // > html.print("<html>\n<head><title>my > > test</title></head>\n<body>"); // html.print("<p><img > > src=\"images/dpt_logo.jpg\"></body></html>"); > > // html.flush(); > > // html.close(); > > > > > > //if details type is summary then output format can only be PDF > > > if(reportsForm.getDetailsType().equals(EMSConstants.REPORTS_SUMMARY)) > > reportsForm.setOutputFormat(EMSConstants.REPORTS_FORMAT_PDF); > > > > //generate the reports using jasper reports > > doJasperReports(reportsForm, request); > > > > CustomerForm customer_form = (CustomerForm)getSessionObject(request, > > "customerForm"); > > Collection all_region_list_forms = > > (Collection)getSessionObject(request, "allRegionListForms"); > > > > admin_form.setCustomerForm(customer_form); > > admin_form.setRegionListForms(all_region_list_forms); > > request.setAttribute(EMSConstants.FORM_VIEW, admin_form); > > > > String relativePath = File.separator + "temp_" + > > request.getSession().getId(); String pdfFilePath = File.separator + > > "temp" + relativePath + File.separator + "ReportinPDF.pdf"; String > > csvFilePath = File.separator + "temp" + relativePath + > File.separator > > + "ReportinCSV.dpt"; > > > > > if(reportsForm.getOutputFormat().equals(EMSConstants.REPORTS_FORMAT_PD > > F)) return (new ActionForward(pdfFilePath, true)); > > > > return (new ActionForward(csvFilePath, true)); } > > > > > > Any help would be appreciated. Thanks. > > > -------------------------------------------------------------- > ---------- > > > > <http://www.digitalpaytech.com/> > > > > > > > > Rizwan Merchant - Software Developer > > 4105 Grandview Highway, Burnaby, BC, V5C 6B4, Canada > > Email: [EMAIL PROTECTED] > > <mailto:[EMAIL PROTECTED]> > > Phone: 604-688-1959 x243 Fax: 604-687-4329 > > Toll Free: 1-888-687-6822 > > Website: www.digitalpaytech.com > <outbind://11/www.digitalpaytech.com> > > > > > > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
