public Optional<Output<LabelSelectorArgs>> namespaceSelector() {
        return Optional.ofNullable(this.namespaceSelector);
    }
@return Selects Namespaces using cluster-scoped labels. This field follows standard label selector semantics; if present but empty, it selects all namespaces.

If PodSelector is also set, then the NetworkPolicyPeer as a whole selects the Pods matching PodSelector in the Namespaces selected by NamespaceSelector. Otherwise it selects all Pods in the Namespaces selected by NamespaceSelector.
sdk/java/src/main/java/com/pulumi/kubernetes/extensions/v1beta1/inputs/NetworkPolicyPeerArgs.java