import org.apache.maven.api.services.ModelProblemCollector;
import org.apache.maven.api.services.model.ModelBuildingEvent;

/**
 * Holds data relevant for a model building event.
 */
record DefaultModelBuildingEvent(
        Model model, Consumer<Model> update, ModelBuilderRequest request, ModelProblemCollector problems)

        if (listener != null) {
            AtomicReference<Model> m = new AtomicReference<>(model);

            ModelBuildingEvent event = new DefaultModelBuildingEvent(model, m::set, request, problems);

            catapult.accept(listener, event);

            return m.get();
        }

        return model;
    }