private com.google.protobuf.SingleFieldBuilderV3<
            com.google.cloud.workstations.v1.WorkstationCluster,
            com.google.cloud.workstations.v1.WorkstationCluster.Builder,
            com.google.cloud.workstations.v1.WorkstationClusterOrBuilder>
        getWorkstationClusterFieldBuilder() {
      if (workstationClusterBuilder_ == null) {
        workstationClusterBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.cloud.workstations.v1.WorkstationCluster,
                com.google.cloud.workstations.v1.WorkstationCluster.Builder,
                com.google.cloud.workstations.v1.WorkstationClusterOrBuilder>(
                getWorkstationCluster(), getParentForChildren(), isClean());
        workstationCluster_ = null;
      }
      return workstationClusterBuilder_;
    }
<pre>
Required. Workstation cluster to create.
</pre>

<code>
.google.cloud.workstations.v1.WorkstationCluster workstation_cluster = 3 [(.google.api.field_behavior) = REQUIRED];
</code>
java-workstations/proto-google-cloud-workstations-v1/src/main/java/com/google/cloud/workstations/v1/CreateWorkstationClusterRequest.java