hibernate/hibernate-orm · error · IllegalArgumentException

Referenced field '${fieldName}' of class '${className}' is n

Error message

Referenced field '${fieldName}' of class '${className}' is not assignable to '${javaTypeName}'

What it means

Error "Referenced field '${fieldName}' of class '${className}' is not assignable to '${javaTypeName}'" thrown in hibernate/hibernate-orm.

Source

Thrown at hibernate-core/src/main/java/org/hibernate/metamodel/model/domain/internal/JpaMetamodelImpl.java:395

						.resolveDescriptor( referencedField.getType() );
			}
		}
		catch (NoSuchFieldException e) {
			// ignore
		}
		return null;
	}

	@Override
	public <E> E getJavaConstant(String className, String fieldName, Class<E> javaTypeClass) {
		try {
			final var referencedField = getJavaField( className, fieldName );
			if ( referencedField == null ) {
				throw new IllegalArgumentException( "Referenced field '" + fieldName
						+ "' of class '" + className + "' does not exist" );
			}
			if ( !javaTypeClass.isAssignableFrom( canonicalize( referencedField.getType() ) ) ) {
				throw new IllegalArgumentException( "Referenced field '" + fieldName
						+ "' of class '" + className
						+ "' is not assignable to '" + javaTypeClass.getTypeName() + "'" );
			}
			return javaTypeClass.cast( referencedField.get( null) );
		}
		catch (NoSuchFieldException | IllegalAccessException e) {
			throw new RuntimeException( e );
		}
	}

	private Field getJavaField(String className, String fieldName) throws NoSuchFieldException {
		final Class<?> namedClass = classLoaderService.classForName( className );
		return namedClass == null ? null : namedClass.getDeclaredField( fieldName );
	}

	@Override
	public void addNamedEntityGraph(String graphName, RootGraphImplementor<?> rootGraph) {
		final var old = entityGraphMap.put( graphName, rootGraph.makeCopy( false, graphName ) );

View on GitHub (pinned to fad1729dce)

Solutions

1. Change the referenced field's type to one assignable to the expected Java type, or fix the expected type in the mapping.

When it happens

Trigger: Thrown when a referenced field exists but its type is not assignable to the expected Java type of the attribute.

Common situations: See trigger scenarios.

AI-assisted analysis of hibernate/hibernate-orm@fad1729dce (2026-08-22). Data as JSON: /api/errors/527a8374f94a3264. Report an issue: GitHub.