@Override
  public int hashCode() {
    return (int) (id ^ (id >>> 32));
  }
Generates a {@link String} representation that uniquely identifies this partition. The string
is in the format of {@code Partition[i]}, where {@code i} is a {@code long} id number uniquely
associated with this partition.
@return The {@link String} representation of this partition.
ambry-clustermap/src/main/java/com/github/ambry/clustermap/Partition.java