@Override
  public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    if (o == null || getClass() != o.getClass()) {
      return false;
    }
    LogSegmentName that = (LogSegmentName) o;
    return position == that.position && generation == that.generation;
  }
@return the name of the file that backs the log segment.
ambry-store/src/main/java/com/github/ambry/store/LogSegmentName.java