private void storeDiffs(Preferences prefs, ImageWriterParam prev, ImageWriterParam param) {
   if (prev != null) {
     PreferencesUtils.storeDiff(prefs, "dcmIIOFormatName", prev.formatName, param.formatName);
     PreferencesUtils.storeDiff(prefs, "dcmJavaClassName", prev.className, param.className);
     PreferencesUtils.storeDiff(prefs, "dcmPatchJPEGLS", prev.patchJPEGLS, param.patchJPEGLS);
     PreferencesUtils.storeDiff(
         prefs, "dcmImageWriteParam", prev.getImageWriteParams(), param.getImageWriteParams());
   } else storeTo(param, prefs);
 }
 private void storeTo(ImageWriterParam param, Preferences prefs) {
   prefs.put("dcmIIOFormatName", param.formatName);
   PreferencesUtils.storeNotNull(prefs, "dcmJavaClassName", param.className);
   PreferencesUtils.storeNotNull(prefs, "dcmPatchJPEGLS", param.patchJPEGLS);
   PreferencesUtils.storeNotEmpty(prefs, "dcmImageWriteParam", param.getImageWriteParams());
 }