I want to open a FileDialog window into the user home folder (i.e. /home/user or /Users/unsername)

I read the user home folder, using System.getProperty:

  String homefolder = System.getProperty(user.home);

And the variable containts the correct home folder. But when i set the filterpath in FileDialog, it opens (in linux) only the /home level not entering into the user home dir.

This is the source code:

  FileDialog dialog = new FileDialog(shell); 
  dialog.setText("Choose a certificate");
  String platform = SWT.getPlatform();
  String homefolder = System.getProperty("user.home");
  dialog.setFilterPath(homefolder);

Any idea? Here a screenshot: