hibernate/hibernate-orm · error · UnsupportedOperationException

Not implemented yet - {}

Error message

Not implemented yet - {}

What it means

Error "Not implemented yet - {}" thrown in hibernate/hibernate-orm.

Source

Thrown at hibernate-core/src/main/java/org/hibernate/query/named/spi/FetchMemento.java:31

/**
 * @author Steve Ebersole
 */
public interface FetchMemento extends ModelPartReferenceMemento {
	/**
	 * The parent node for the fetch
	 */
	interface Parent extends ModelPartReferenceMemento {
		Class<?> getResultJavaType();
	}

	/**
	 * Resolve the fetch-memento into the result-graph-node builder
	 */
	FetchBuilder resolve(Parent parent, Consumer<String> querySpaceConsumer, ResultSetMappingResolutionContext context);

	default MemberMapping<?> toJpaMemberMapping(Parent parent, SessionFactory sessionFactory) {
		throw new UnsupportedOperationException( "Not implemented yet - " + getClass().getName() );
	}
}

View on GitHub (pinned to fad1729dce)

Solutions

1. This fetch memento operation is not implemented. Avoid this code path or upgrade to a Hibernate version that implements it.

When it happens

Trigger: A code path that Hibernate has not implemented is exercised: Not implemented yet - <value>

Common situations: Using newer/edge API features (certain projections, specifications, fetch mementos, composite-path native mappings, null keys in key-based pagination) that are present but not yet implemented.

AI-assisted analysis of hibernate/hibernate-orm@fad1729dce (2026-08-22). Data as JSON: /api/errors/329a4bb894e35257. Report an issue: GitHub.