title: Spring MVC - How to show a message in view until a download starts
body: <p>I have a Controller which allows users to download a file.
  The problem is that depending on the params sent to the controller, the controller will zip different folders and send them to the clients, and zipping can take sometimes 2 minutes, time while the user is prompted with an empty browser tab and a loading header.</p>
  
  <p>Is there a way I could show a message to the user until the file is zipped and download really starts? Something like "Please wait, your file is being prepared for download!"</p>
  
  <p>Thank you!</p>