private OnnxEvaluator evaluator() {
        if (evaluator == null) {
            throw new IllegalStateException("ONNX model has not been loaded.");
        }
        return evaluator;
    }
A named ONNX model that should be evaluated with OnnxEvaluator.

@author lesters
model-evaluation/src/main/java/ai/vespa/models/evaluation/OnnxModel.java