private com.google.protobuf.SingleFieldBuilderV3<
            com.google.rpc.Status, com.google.rpc.Status.Builder, com.google.rpc.StatusOrBuilder>
        getIndexErrorFieldBuilder() {
      if (indexErrorBuilder_ == null) {
        indexErrorBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.rpc.Status,
                com.google.rpc.Status.Builder,
                com.google.rpc.StatusOrBuilder>(getIndexError(), getParentForChildren(), isClean());
        indexError_ = null;
      }
      return indexErrorBuilder_;
    }
<pre>
Output only. If there was an error with indexing the product set, the field
is populated.

This field is ignored when creating a ProductSet.
</pre>

<code>.google.rpc.Status index_error = 4 [(.google.api.field_behavior) = OUTPUT_ONLY];</code>
java-vision/proto-google-cloud-vision-v1p3beta1/src/main/java/com/google/cloud/vision/v1p3beta1/ProductSet.java