In Hazelcast the data is split up in partitions: by default, 271 and configurable through the 'hazelcast.partition.count'
GroupProperty. Each partition is owned by one member and the ownership can change if members join or leave the cluster.
Using this Partition object, you get access to who is the owner of a given partition. This object is not a DTO, so it will
be updated when a member changes ownership.