public boolean save()
   {
      Preferences prefs = Preferences.userNodeForPackage(Joculus.class);
      
      boolean save_ok = true;

      save_ok = save_general_prefs(prefs);      
      save_ok = save_editor_prefs(prefs);
      save_ok = save_window_prefs(prefs);
      save_ok = save_processor_prefs(prefs);
      save_ok = save_css_prefs(prefs);

      // write all changes.
      try
      {
         prefs.flush();
      }
      catch (BackingStoreException ex)
      {
         Joculus.showError(UIStrings.ERROR_WRITE_SETTINGS_FAILED + "\n" + ex.getMessage());
         return false;
      }
      return true;
   }