hibernate/hibernate-orm · error · IllegalArgumentException

Entity class may not be null

Error message

Entity class may not be null

What it means

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

Source

Thrown at hibernate-core/src/main/java/org/hibernate/internal/SessionImpl.java:2211

	@Override
	@Nullable
	public <T> T find(
			@Nonnull Class<T> entityClass,
			@Nonnull Object primaryKey,
			@Nonnull LockModeType lockModeType,
			@Nullable Map<String, Object> properties) {
		//noinspection ConstantValue
		if ( lockModeType == null ) {
			throw new IllegalArgumentException("Given LockModeType was null");
		}
		return doFind( entityClass, primaryKey, LockMode.fromJpaLockMode( lockModeType ), properties );
	}

	private <T> T doFind(Class<T> entityClass, Object primaryKey, LockMode lockMode, Map<String, Object> properties) {
		checkOpen();
		if ( entityClass == null ) {
			throw new IllegalArgumentException( "Entity class may not be null" );
		}
		final var options = determineFindOptions( lockMode, properties );
		final var entityDescriptor = requireEntityPersisterForLoad( entityClass );
		return byKeyWithGraph( entityClass, entityDescriptor, properties, options )
				.performFind( primaryKey );
	}

	private <T> FindByKeyOperation<T> byKeyWithGraph(
			Class<T> entityClass,
			EntityPersister entityDescriptor,
			Map<String, Object> properties,
			FindOption[] options) {
		final var fetchHint = fetchGraphFromHints( properties );
		final var loadHint = loadGraphFromHints( properties );
		final GraphSemantic graphSemantic;
		final RootGraphImplementor<?> graph;
		if ( fetchHint != null ) {
			if ( loadHint != null ) {

View on GitHub (pinned to fad1729dce)

Solutions

  1. Supply the entity class explicitly (e.g. session.find(MyEntity.class, id)) rather than null.
  2. Verify the class object is not null before the call.

When it happens

Trigger: Thrown at hibernate-core/src/main/java/org/hibernate/internal/SessionImpl.java:2211 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/b9c3d0a122aeacba. Report an issue: GitHub.