@Override
        public boolean equals(Object obj) {
            if (obj == null)
                return false;

            if (!getClass().isInstance(obj))
                return false;

            MemberPair otherPair = (MemberPair) obj;
            return this.srcMemberId.equals(otherPair.srcMemberId) && this.dstMemberId.equals(otherPair.dstMemberId);
        }
This class represents a pair of member Ids involved in a partition reassignment.
Each pair contains a source and a destination member Id.
It normally corresponds to a particular partition or topic, and indicates that the particular partition or some
partition of the particular topic was moved from the source member to the destination member during the rebalance.
group-coordinator/src/main/java/org/apache/kafka/coordinator/group/assignor/UniformHeterogeneousAssignmentBuilder.java