Wolfgang Seifert ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=635f717... ) *created* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiNzU3NmE2ZmZm... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-15710?atlOrigin=eyJpIjoiNzU3Nm... ) HHH-15710 ( https://hibernate.atlassian.net/browse/HHH-15710?atlOrigin=eyJpIjoiNzU3Nm... ) ReflectHelper and RegistryHelper do not handle generic types correctly ( https://hibernate.atlassian.net/browse/HHH-15710?atlOrigin=eyJpIjoiNzU3Nm... ) Issue Type: Bug Affects Versions: 6.1.5 Assignee: Unassigned Components: hibernate-core Created: 11/Nov/2022 23:26 PM Environment: hibernate 6.1.5 orm, jdk 17 Priority: Major Reporter: Wolfgang Seifert ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=635f717... ) This issue is a result of further investigating https://hibernate.atlassian.net/browse/HHH-15646 ( https://hibernate.atlassian.net/browse/HHH-15646 ). The Exceptions are thrown from ReflectHelper and RegistryHelper. Changing ReflectHelper to public static <T> Class<T> getClass(java.lang.reflect.Type type) { if ( type == null ) { return null; } else if ( type instanceof Class<?> ) { return (Class<T>) type; } else if ( type instanceof TypeVariable<?>) { return getClass( ( (TypeVariable) type ).getBounds()[0]); } else if ( type instanceof ParameterizedType ) { return (Class<T>) ( (ParameterizedType) type ).getRawType(); } throw new UnsupportedOperationException( "Can't get java type class from type: " + type ); } and RegistryHelper to private <J> Class<J> determineJavaTypeClass(Type javaType) { final Class<J> javaTypeClass; if ( javaType instanceof Class<?> ) { javaTypeClass = (Class<J>) javaType; } else if ( javaType instanceof TypeVariable<?>){ final TypeVariable typeVariable = (TypeVariable) javaType; javaTypeClass = determineJavaTypeClass(typeVariable.getBounds()[0]); } else { final ParameterizedType parameterizedType = (ParameterizedType) javaType; javaTypeClass = (Class<J>) parameterizedType.getRawType(); } return javaTypeClass; } resolves the issue, but getBounds() [0] is certainly not a safe solution. An expert is needed here. ( https://hibernate.atlassian.net/browse/HHH-15710#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-15710#add-comment?atlOrigin=ey... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100210- sha1:583150f )