private com.google.protobuf.SingleFieldBuilderV3<
              com.google.protobuf.Timestamp,
              com.google.protobuf.Timestamp.Builder,
              com.google.protobuf.TimestampOrBuilder>
          getLastUpdateTimeFieldBuilder() {
        if (lastUpdateTimeBuilder_ == null) {
          lastUpdateTimeBuilder_ =
              new com.google.protobuf.SingleFieldBuilderV3<
                  com.google.protobuf.Timestamp,
                  com.google.protobuf.Timestamp.Builder,
                  com.google.protobuf.TimestampOrBuilder>(
                  getLastUpdateTime(), getParentForChildren(), isClean());
          lastUpdateTime_ = null;
        }
        return lastUpdateTimeBuilder_;
      }
<pre>
Output only. The time at which the status was last updated.
</pre>

<code>
.google.protobuf.Timestamp last_update_time = 2 [(.google.api.field_behavior) = OUTPUT_ONLY];
</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/DeployedModel.java