private @Nullable Insets editInsets(String key, String value) {
        String newValue = Messages.showInputDialog(getRootPane(),
                                                   IdeBundle.message("dialog.message.enter.new.value.for.0.in.form.top.left.bottom.right",
                                                                     key),
                                                   IdeBundle.message("dialog.title.insets.editor"), null, value,
                                                   new InputValidator() {
                                                     @Override
                                                     public boolean checkInput(String inputString) {
                                                       return parseInsets(inputString) != null;
                                                     }

                                                     @Override
                                                     public boolean canClose(String inputString) {
                                                       return checkInput(inputString);
                                                     }
                                                   });

        return newValue != null ? parseInsets(newValue) : null;
      }
private @Nullable Insets editInsets(String key, String value)