hibernate/hibernate-orm · error · IllegalArgumentException

null key for collection: {}

Error message

null key for collection: {}

What it means

Error "null key for collection: {}" thrown in hibernate/hibernate-orm.

Source

Thrown at hibernate-core/src/main/java/org/hibernate/persister/collection/mutation/HistoryCollectionRowMutationHelper.java:56

		this.mutationTarget = mutationTarget;
		this.attributeMapping = mutationTarget.getTargetPart();
		this.temporalMapping = attributeMapping.getTemporalMapping();
		this.historyTableName = historyTableName;
		this.currentTableName = mutationTarget.getCollectionTableMapping().getTableName();
		this.indexColumnIsSettable = indexColumnIsSettable;
		this.elementColumnIsSettable = elementColumnIsSettable;
		this.indexIncrementer = indexIncrementer;
	}

	void bindInsertValues(
			PersistentCollection<?> collection,
			Object key,
			Object rowValue,
			int rowPosition,
			SharedSessionContractImplementor session,
			JdbcValueBindings jdbcValueBindings) {
		if ( key == null ) {
			throw new IllegalArgumentException( "null key for collection: " + mutationTarget.getRolePath() );
		}
		attributeMapping.getKeyDescriptor().getKeyPart().decompose(
				key,
				0,
				jdbcValueBindings,
				null,
				this::bindSetValue,
				session
		);

		final var identifierDescriptor = attributeMapping.getIdentifierDescriptor();
		if ( identifierDescriptor != null ) {
			identifierDescriptor.decompose(
					collection.getIdentifier( rowValue, rowPosition ),
					0,
					jdbcValueBindings,
					null,
					this::bindSetValue,

View on GitHub (pinned to fad1729dce)

Solutions

1. Ensure the owning entity's identifier is non-null before the history collection rows are written (persist the owner first).

When it happens

Trigger: Thrown when mutating a history collection row with a null collection key, indicating the owner entity has no identifier value.

Common situations: See trigger scenarios.

AI-assisted analysis of hibernate/hibernate-orm@fad1729dce (2026-08-22). Data as JSON: /api/errors/8f58270545ade6a2. Report an issue: GitHub.