@Override
  public boolean isDirtyStamp(@NotNull Stamp stamp, File file) throws IOException {
    if (!(stamp instanceof HashStamp)) return true;
    HashStamp filesStamp = (HashStamp)stamp;
    if (!myTimestampStorage.isDirtyStamp(FileTimestamp.fromLong(filesStamp.myTimestamp), file)) return false;
    Long hash = filesStamp.myHash;
    if (hash == null) return true;
    return hash != getFileHash(file);
  }
@Override
  public boolean isDirtyStamp(@NotNull Stamp stamp, File file)