public String topologyKey() {
        return this.topologyKey;
    }
@return TopologyKey is the key of node labels. Nodes that have a label with this key and identical values are considered to be in the same topology. We consider each &lt;key, value&gt; as a &#34;bucket&#34;, and try to put balanced number of pods into each bucket. We define a domain as a particular instance of a topology. Also, we define an eligible domain as a domain whose nodes meet the requirements of nodeAffinityPolicy and nodeTaintsPolicy. e.g. If TopologyKey is &#34;kubernetes.io/hostname&#34;, each Node is a domain of that topology. And, if TopologyKey is &#34;topology.kubernetes.io/zone&#34;, each zone is a domain of that topology. It&#39;s a required field.
sdk/java/src/main/java/com/pulumi/kubernetes/core/v1/outputs/TopologySpreadConstraint.java