hibernate/hibernate-orm · error · IllegalArgumentException

Couldn't determine basic type for java type: {}

Error message

Couldn't determine basic type for java type: {}

What it means

SqmExpression.cast(Class) resolves the target Java type through the session's TypeConfiguration via getBasicTypeForJavaType(). Only classes with a registered BasicType can serve as cast targets; for anything else (entity classes, embeddables, interfaces, arbitrary POJOs, unregistered custom types) Hibernate cannot build a cast expression and throws IllegalArgumentException naming the class.

Source

Thrown at hibernate-core/src/main/java/org/hibernate/query/sqm/tree/spi/expression/SqmExpression.java:165

			// safe cast, because we just checked
			@SuppressWarnings("unchecked")
			final SqmExpression<X> castExpression = (SqmExpression<X>) this;
			return castExpression;
		}
		else {
			final QueryEngine queryEngine = nodeBuilder().getQueryEngine();
			final SqmCastTarget<?> target = new SqmCastTarget<>( (ReturnableType<?>) type, nodeBuilder() );
			return queryEngine.getSqmFunctionRegistry().getFunctionDescriptor( "cast" )
					.generateSqmExpression( asList( this, target ), (ReturnableType<X>) type, queryEngine );
		}
	}

	@Nonnull
	@Override
	default <X> SqmExpression<X> cast(@Nonnull Class<X> type) {
		final BasicType<X> basicType = nodeBuilder().getTypeConfiguration().getBasicTypeForJavaType( type );
		if ( basicType == null ) {
			throw new IllegalArgumentException( "Couldn't determine basic type for java type: " + type.getName() );
		}
		return castAs( basicType );
	}

	@Nonnull
	@Override
	JpaPredicate notEqualTo(@Nonnull Expression<?> value);

	@Nonnull
	@Override
	JpaPredicate notEqualTo(Object value);
}

View on GitHub (pinned to fad1729dce)

Solutions

1. Cast to a standard basic type instead (String, Integer, Long, Double, BigDecimal, Boolean, dates).
2. Resolve the BasicType explicitly and use castAs(): BasicType<X> t = nodeBuilder().getTypeConfiguration().getBasicTypeForJavaType(X.class); if non-null, call expr.castAs(t).
3. Register a JavaType/BasicType for the class globally with @JavaTypeRegistration (or map it with an AttributeConverter) so the lookup succeeds.
4. For entity types use treatAs()/type() constructs rather than cast().

Example fix

// before
SqmExpression<Money> e = expr.cast( Money.class ); // no BasicType for Money -> IllegalArgumentException

// after - resolve the registered basic type and cast with it
BasicType<Money> moneyType = nodeBuilder().getTypeConfiguration()
        .getBasicTypeForJavaType( Money.class );
SqmExpression<Money> e = expr.castAs( moneyType ); // register the type first if moneyType == null

BasicType<X> basicType = nodeBuilder().getTypeConfiguration().getBasicTypeForJavaType( type );
if ( basicType == null ) {
    throw new IllegalArgumentException( "No basic type registered for " + type.getName()
            + " - cast to a standard type or register a @JavaTypeRegistration" );
}
return expr.castAs( basicType );

static boolean isCastableToBasicType(NodeBuilder nb, Class<?> javaType) {
    return nb.getTypeConfiguration().getBasicTypeForJavaType( javaType ) != null;
}

When it happens

Trigger: Calling expression.cast(X.class) where X has no registered basic type: casting to an entity or embeddable class, to Object or Serializable, to an array type, to a custom value class without @JavaTypeRegistration/@Converter mapping, or to a java.time/jdbc type the current dialect does not register.

Common situations: Cast targets chosen dynamically at runtime (the Class comes from a variable or user input); attempts to widen an expression by casting to Object; custom types registered only for specific dialects or lost during refactors; Hibernate upgrades where a formerly registered default type disappeared.

Related errors

• Enum literal cannot be cast to BigDecimal
• Enum literal cannot be cast to BigInteger
• MappedSuperclassType cannot be used to create an SqmPath - t
• LHS cannot be null for a sub-navigable reference - {}
• Not correlated

AI-assisted analysis of hibernate/hibernate-orm@fad1729dce (2026-08-22). Data as JSON: /api/errors/5c51711e293134b7. Report an issue: GitHub.