title: Convert between URL and windows filename (Java)?
body: <p>Is there a standard/good way of converting between urls and windows filenames, in Java?  </p>
  
  <p>I am trying to download files, but I want the windows filename to be convertible back to the original filename.  Note that the query portion of the url is vital, as I will be downloading different pages that differ only in query.</p>
  
  <p>My current hacky solution is to replace illegal characters (such as '?') with a specific string (such as 'QQ'), but this makes conversion back to url less transparent.  Is there a better way?</p>