public com.google.protobuf.ByteString getProducerNodeBytes() {
          java.lang.Object ref = producerNode_;
          if (ref instanceof String) {
            com.google.protobuf.ByteString b =
                com.google.protobuf.ByteString.copyFromUtf8((java.lang.String) ref);
            producerNode_ = b;
            return b;
          } else {
            return (com.google.protobuf.ByteString) ref;
          }
        }
<pre>
The name of graph node who produces the output resource name.
For example:
output_resource:
/projects/123/locations/us-central1/corpora/my-corpus/dataSchemas/my-schema
producer_node: occupancy-count
</pre>

<code>string producer_node = 2;</code>

@return The bytes for producerNode.
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/Application.java