private com.google.protobuf.SingleFieldBuilderV3<
            com.google.cloud.visionai.v1.Draft,
            com.google.cloud.visionai.v1.Draft.Builder,
            com.google.cloud.visionai.v1.DraftOrBuilder>
        getDraftFieldBuilder() {
      if (draftBuilder_ == null) {
        draftBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.cloud.visionai.v1.Draft,
                com.google.cloud.visionai.v1.Draft.Builder,
                com.google.cloud.visionai.v1.DraftOrBuilder>(
                getDraft(), getParentForChildren(), isClean());
        draft_ = null;
      }
      return draftBuilder_;
    }
<pre>
Required. The resource being updated.
</pre>

<code>.google.cloud.visionai.v1.Draft draft = 2 [(.google.api.field_behavior) = REQUIRED];
</code>
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/UpdateDraftRequest.java