@Override
    public TimestampPerTarget[] read(@NotNull DataInput in) throws IOException {
      int size = in.readInt();
      TimestampPerTarget[] targets = new TimestampPerTarget[size];
      for (int i = 0; i < size; i++) {
        int id = in.readInt();
        long timestamp = in.readLong();
        targets[i] = new TimestampPerTarget(id, timestamp);
      }
      return targets;
    }
@Override
    public TimestampPerTarget[] read(@NotNull DataInput in)