private void ensureForwardingRulesIsMutable() {
      if (!((bitField0_ & 0x00000008) != 0)) {
        forwardingRules_ =
            new java.util.ArrayList<com.google.cloud.vmwareengine.v1.DnsForwarding.ForwardingRule>(
                forwardingRules_);
        bitField0_ |= 0x00000008;
      }
    }
<pre>
Output only. Last update time of this resource.
</pre>

<code>
.google.protobuf.Timestamp update_time = 3 [(.google.api.field_behavior) = OUTPUT_ONLY];
</code>
java-vmwareengine/proto-google-cloud-vmwareengine-v1/src/main/java/com/google/cloud/vmwareengine/v1/DnsForwarding.java