hibernate/hibernate-orm · error · IllegalArgumentException

Entity may not be null

Error message

Entity may not be null

What it means

Error "Entity may not be null" thrown in hibernate/hibernate-orm.

Source

Thrown at hibernate-core/src/main/java/org/hibernate/internal/StatelessSessionImpl.java:1637

	public String bestGuessEntityName(@Nonnull Object object) {
		final var lazyInitializer = extractLazyInitializer( object );
		return guessEntityName( lazyInitializer == null
				? object
				: lazyInitializer.getImplementation() );
	}

	@Override
	public Object getContextEntityIdentifier(@Nonnull Object object) {
		checkOpen();
		return null;
	}

	@Override
	public String guessEntityName(@Nonnull Object entity) {
		checkOpen();
		//noinspection ConstantValue
		if ( entity == null ) {
			throw new IllegalArgumentException( "Entity may not be null" );
		}
		return entity.getClass().getName();
	}

	@Override
	@Nonnull
	public EntityPersister getEntityPersister(@Nullable String entityName, @Nonnull Object entity) {
		checkOpen();
		//noinspection ConstantValue
		if ( entity == null ) {
			throw new IllegalArgumentException( "Entity may not be null" );
		}
		return entityName == null
				? requireEntityPersister( guessEntityName( entity ) )
				: requireEntityPersister( entityName ).getSubclassEntityPersister( entity, getFactory() );
	}

	@Override

View on GitHub (pinned to fad1729dce)

Solutions

1. Pass a non-null entity instance to the StatelessSession operation; null-check before the call.

When it happens

Trigger: Thrown at hibernate-core/src/main/java/org/hibernate/internal/StatelessSessionImpl.java:1637 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of hibernate/hibernate-orm@fad1729dce (2026-08-22). Data as JSON: /api/errors/5c2172a66f021247. Report an issue: GitHub.