Grails File Upload Problems

Question

I\'m trying to emulate the file upload code from the grails website, and I\'m running into some problems. I\'m using the same code as found here. Here is my code:

Answer 1

Problem solved!

I was using the example code for uploading files to Grails differently than the original author probably intended. The problem is that when the upload method of the controller was called, it was sometimes for the original render of the Upload page. The request in that method was was not of type MultipartHttpServletRequest. When I did a POST with my file to upload, then Spring did the correct thing and changed my requestion to MultipartHttpServletRequest. So, I needed to do a simple check in my update controller method before using my request like a MultipartHttpServletRequest.

if(request instanceof MultipartHttpServletRequest)
{
  MultipartHttpServletRequest mpr = (MultipartHttpServletRequest)request;  
  CommonsMultipartFile f = (CommonsMultipartFile) mpr.getFile("myFile");
  if(!f.empty)
    flash.message = 'success'
  else
   flash.message = 'file cannot be empty'
}   
else
  flash.message = 'request is not of type MultipartHttpServletRequest'