public com.google.cloud.tpu.v2alpha1.UpcomingMaintenance getUpcomingMaintenance() {
      if (upcomingMaintenanceBuilder_ == null) {
        return upcomingMaintenance_ == null
            ? com.google.cloud.tpu.v2alpha1.UpcomingMaintenance.getDefaultInstance()
            : upcomingMaintenance_;
      } else {
        return upcomingMaintenanceBuilder_.getMessage();
      }
    }
<pre>
Output only. Upcoming maintenance on this TPU node.
</pre>

<code>
.google.cloud.tpu.v2alpha1.UpcomingMaintenance upcoming_maintenance = 51 [(.google.api.field_behavior) = OUTPUT_ONLY];
</code>

@return The upcomingMaintenance.
java-tpu/proto-google-cloud-tpu-v2alpha1/src/main/java/com/google/cloud/tpu/v2alpha1/Node.java