hibernate/hibernate-orm · error · MappingException

Entity [%s] did not define an identifier

Error message

Entity [%s] did not define an identifier

What it means

Error "Entity [%s] did not define an identifier" thrown in hibernate/hibernate-orm.

Source

Thrown at hibernate-core/src/main/java/org/hibernate/boot/model/source/internal/hbm/EntityHierarchySourceImpl.java:87

		this.caching = Helper.createCaching( entityElement().getCache() );
		this.naturalIdCaching = Helper.createNaturalIdCaching(
				rootEntitySource.jaxbEntityMapping().getNaturalIdCache()
		);

		collectedEntityNames.add( rootEntitySource.getEntityNamingSource().getEntityName() );
	}

	public MappingDocument getRootEntityMappingDocument() {
		return rootEntityMappingDocument;
	}

	private static IdentifierSource interpretIdentifierSource(RootEntitySourceImpl rootEntitySource) {
		final JaxbHbmSimpleIdType simpleId = rootEntitySource.jaxbEntityMapping().getId();
		final JaxbHbmCompositeIdType compositeId = rootEntitySource.jaxbEntityMapping().getCompositeId();

		if ( simpleId == null && compositeId == null ) {
			throw new MappingException(
					String.format(
							Locale.ROOT,
							"Entity [%s] did not define an identifier",
							rootEntitySource.getEntityNamingSource().getEntityName()
					),
					rootEntitySource.origin()
			);
		}

		if ( simpleId != null ) {
			return new IdentifierSourceSimpleImpl( rootEntitySource );
		}
		else {
			// if we get here, we should have a composite identifier.  Just need
			// to determine if it is aggregated, or non-aggregated...

			if ( compositeId.isMapped() ) {
				if ( StringHelper.isEmpty( compositeId.getClazz() ) ) {

View on GitHub (pinned to fad1729dce)

Solutions

1. Add an <id/> (or <composite-id/>) mapping for the entity in the hbm.xml document.

Example fix

Add an <id/> (or <composite-id/>) mapping for the entity in the hbm.xml document.

When it happens

Trigger: An hbm.xml / orm.xml mapping document violates a mapping rule during bootstrap.

Common situations: Legacy XML mappings with invalid combinations (column+formula, mixed inheritance, missing identifiers, bad extends references).

AI-assisted analysis of hibernate/hibernate-orm@fad1729dce (2026-08-22). Data as JSON: /api/errors/2dde6002eedfe85b. Report an issue: GitHub.