@Override
    public int hashCode() {
        return name.hashCode() +
                17 * index +
                23 * distribution.hashCode() +
                43 * subgroups.hashCode() +
                47 * nodes.hashCode();

    }
Represent a group in the tree structure of groups in hierarchical setup of VDS nodes.
vdslib/src/main/java/com/yahoo/vdslib/distribution/Group.java