@Override
  public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    if (o == null || getClass() != o.getClass()) {
      return false;
    }
    ChunkInfo chunkInfo = (ChunkInfo) o;
    return chunkSizeInBytes == chunkInfo.chunkSizeInBytes && expirationTimeInMs == chunkInfo.expirationTimeInMs
        && Objects.equals(blobId, chunkInfo.blobId) && Objects.equals(reservedMetadataId, chunkInfo.reservedMetadataId);
  }
@return the reserved metadata id of the chunk.
ambry-api/src/main/java/com/github/ambry/router/ChunkInfo.java