private com.google.protobuf.SingleFieldBuilderV3<
            com.google.cloud.video.livestream.v1.RetentionConfig,
            com.google.cloud.video.livestream.v1.RetentionConfig.Builder,
            com.google.cloud.video.livestream.v1.RetentionConfigOrBuilder>
        getRetentionConfigFieldBuilder() {
      if (retentionConfigBuilder_ == null) {
        retentionConfigBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.cloud.video.livestream.v1.RetentionConfig,
                com.google.cloud.video.livestream.v1.RetentionConfig.Builder,
                com.google.cloud.video.livestream.v1.RetentionConfigOrBuilder>(
                getRetentionConfig(), getParentForChildren(), isClean());
        retentionConfig_ = null;
      }
      return retentionConfigBuilder_;
    }
<pre>
Optional. Configuration for retention of output files for this channel.
</pre>

<code>
.google.cloud.video.livestream.v1.RetentionConfig retention_config = 26 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-video-live-stream/proto-google-cloud-live-stream-v1/src/main/java/com/google/cloud/video/livestream/v1/Channel.java