@Override
  public String toString() {
    StringBuilder sb = new StringBuilder();
    sb.append("FileInfo{")
      .append("fileName='").append(fileName).append('\'')
      .append(", fileSize=").append(fileSize)
      .append('}');
    return sb.toString();
  }
Get the size of the file
ambry-api/src/main/java/com/github/ambry/store/StoreFileInfo.java