@Nullable
  private Pair<String, String> doAddOrEdit(@Nullable Pair<String, String> o) {
    EditMavenPropertyDialog d = new EditMavenPropertyDialog(o, myAvailableProperties);
    if (!d.showAndGet()) {
      return null;
    }
    return d.getValue();
  }
@Nullable
  private Pair<String, String> doAddOrEdit(@Nullable Pair<String, String> o)