public void copyFrom(@NotNull SvnMapping other) {
    myFile2UrlMap.clear();
    myUrl2FileMap.clear();
    myLonelyRoots.clear();

    myFile2UrlMap.putAll(other.myFile2UrlMap);
    myUrl2FileMap.putAll(other.myUrl2FileMap);
    myLonelyRoots.addAll(other.myLonelyRoots);
    myPreCalculatedUnderVcsRoots.drop();
  }
public void copyFrom(@NotNull SvnMapping other)