public com.google.protobuf.DurationOrBuilder getDurationOrBuilder() {
        if (durationBuilder_ != null) {
          return durationBuilder_.getMessageOrBuilder();
        } else {
          return duration_ == null ? com.google.protobuf.Duration.getDefaultInstance() : duration_;
        }
      }
<pre>
Duration of an ad opportunity. Must be greater than 0.
</pre>

<code>.google.protobuf.Duration duration = 1;</code>
java-video-live-stream/proto-google-cloud-live-stream-v1/src/main/java/com/google/cloud/video/livestream/v1/Event.java