Session making triouble while downloading files successively

Question

hi, i m hving some problems with file downloading.... my code that saves bytes array into the session is as follows
byte[] bytes = proposalService.getDownload(fileName); // a method that returns bytes array
            Object bt = request.getSession(false).getAttribute("bytes");
            if(bt != null){
                request.getSession(false).setAttribute("bytes", null);
                request.getSession(false).removeAttribute("bytes");
            request.getSession(false).setAttribute("bytes", bytes);
            bytes = null;
            try {
                response.sendRedirect("FileDownload");
            } catch (IOException ex) {
                ex.printStackTrace();
            } catch (Exception e) {
                e.printStackTrace();
            }and the servlet that gets the data from session are able to download
StringBuffer xlsFile = null;
        HttpSession session = null;
        StringBuffer xlsFileHeader = null;
        try {
            xlsFile = new StringBuffer();
            xlsFile.append("MI_Tariff"+new Date().getTime());
            xlsFile.append(".xls");
            response.setHeader("Cache-Control", "max-age=30");
            response.setContentType("application/xls");
            xlsFileHeader = new StringBuffer();
            xlsFileHeader.append("attachment; filename="+xlsFile);
            response.setHeader("Content-disposition", xlsFileHeader.toString());
            session = request.getSession(false);
            byte[] bytes = (byte[]) session.getAttribute("bytes");
            System.out.println("----------------------------"+bytes.length);
            if(bytes !=null && bytes.length > 0) {
                response.setContentLength(bytes.length);
                ServletOutputStream servletOutputStream = response.getOutputStream();
                servletOutputStream.write(bytes, 0, bytes.length);
            bytes = null;
        } catch(Exception e){
            e.printStackTrace();
        } finally{
            session.setAttribute("bytes",null);
            session.removeAttribute("bytes");
            xlsFile = null;
            xlsFileHeader = null;
        }the problem is i m using this code to download 3 files one by one ... some times it returns the proper file that i want to download but sometime last downloaded file is again downloaded....
i debug this code thoroughlly each time new file is fetched and stored in to the session but when the servlet code runs there might be some problems due to which the bytes array remains empty and it returns the last file downloaded....
as u can see bytes are being removed proporly but i think the problem is with session ... it might use diffrent session for retrieving and saving the bytes array.. HOW CAN I SOLVE THIS PROBLEM....
All the suggestions are eagerly welcomed
Thanks in advance

Answer 1

Just realized that I forgot to give the link to the file servlet earlier; take a look at this code:
http://balusc.blogspot.com/2007/07/fileservlet.html
And no, sorry if you thought that was for you personally; I try to put that in every post of mine so that at least some of the new users go and take a look. If you look at most posts on the forums, there are a lot of replies asking the posters to:
- use code tags
- use proper language ( i.e.complete words and not 'u' , 'plz' etc )
- give the problem details clearly
- give stack traces
etc.
Since this resource is already available, I put this up with my posts instead of repeating the same things 50 times a day. It's like a pseudo-signature :)
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