page caching

[Kim Kantola]

I am opening a spreadsheet from my servlet by using :
res.setContentType("application/vnd.ms-excel");
The problem I am having is that after I hit the back button on IE, and then try to redirect to my spreadsheet page a subsequent time, I get the first spreadsheet page contents instead of the new content I expect. It seems that the page is caching, but I am not sure how to resolve that. Any ideas would be appreciated.

[Manuel Moons]

Try adding this to your code:

 
//date in the past...
response.addHeader("Expires", "Mon, 26 Jul 1997 05:00:00 GMT");
//always modified
response.addHeader("Last-Modified", new java.util.Date().toGMTString());

//HTTP/1.1 
response.addHeader("Cache-Control", "no-cache, must-revalidate");
//HTTP/1.0 
response.addHeader("Pragma", "no-cache"); 

[Kim Kantola]

Hi,
Thank you very much for your idea. It makes sense that the suggestion should work, but for some reason it didn't. I am not sure if something is up with my environment which is causing a problem. I did find a differant solution, which I thought I would post here in case anyone else is having a similar problem. I added a header to the response that redirects the data to a seperate spreadsheet file, instead of opening the spreadsheet from within the browser. This seems to have done the trick. Here is the code:

 
  res.setHeader ("Content-Transfer-Encoding","7bit"); 
  res.setHeader ("Content-Disposition","attachment;filename=\"exit41report.xls\""); 

[Kim Kantola]

Just for the record, wanted to note that this was found to be an environment problem, not sure what, something with my browser I am guessing. This code worked on another machine in my office.
Again, thank you very much for your time.