quarkusio/quarkus · error · RuntimeException

${classInfo.name()} should only extend REST Data Panache int

Error message

${classInfo.name()} should only extend REST Data Panache interface

What it means

validateResource enforces that a REST Data Panache resource interface extends exactly one interface. Extending more than one interface breaks the generic signature extraction, so the build fails with this RuntimeException.

Source

Thrown at extensions/panache/hibernate-orm-rest-data-panache/deployment/src/main/java/io/quarkus/hibernate/orm/rest/data/panache/deployment/HibernateOrmPanacheRestProcessor.java:153

            String resourceClass = resourceImplementor.implement(
                    classOutput, dataAccessImplementor, resourceInterface, entityType, listenersForEntityType);
            // Make sure that repository bean is not removed and will be injected to the generated resource
            unremovableBeansProducer.produce(new UnremovableBeanBuildItem(
                    new UnremovableBeanBuildItem.BeanClassNameExclusion(repositoryClassName)));

            restDataResourceProducer.produce(new RestDataResourceBuildItem(
                    new ResourceMetadata(resourceClass, resourceInterface, entityType, idType,
                            getEntityFields(index.getIndex(), entityType))));
        }
    }

    private void validateResource(IndexView index, ClassInfo classInfo) {
        if (!Modifier.isInterface(classInfo.flags())) {
            throw new RuntimeException(classInfo.name() + " has to be an interface");
        }

        if (classInfo.interfaceNames().size() > 1) {
            throw new RuntimeException(classInfo.name() + " should only extend REST Data Panache interface");
        }

        if (!index.getKnownDirectImplementors(classInfo.name()).isEmpty()) {
            throw new RuntimeException(classInfo.name() + " should not be extended or implemented");
        }
    }

    private List<Type> getGenericTypes(ClassInfo classInfo) {
        return classInfo.interfaceTypes()
                .stream()
                .findFirst()
                .orElseThrow(() -> new RuntimeException(classInfo.toString() + " does not have generic types"))
                .asParameterizedType()
                .arguments();
    }
}

View on GitHub (pinned to e1c734241f)

Solutions

1. Remove all but the single REST Data Panache interface from the extends clause
2. Move shared methods to the entity or a separate service, not the resource interface
3. Split into multiple resource interfaces if two domains are needed

Example fix

// before
public interface PersonResource extends PanacheEntityResource<Person, Long>, Serializable {}
// after
public interface PersonResource extends PanacheEntityResource<Person, Long> {}

if (resourceClass.getInterfaces().length != 1)
    throw new IllegalStateException(resourceClass + " must extend exactly one Panache REST Data interface");

When it happens

Trigger: A resource interface extending two or more interfaces, e.g. 'interface PersonResource extends PanacheEntityResource<Person, Long>, Serializable' or extending two Panache resource interfaces.

Common situations: Adding Serializable/Comparable to a resource interface; composing several resource interfaces into one.

Related errors

• ${classInfo.name()} has to be an interface
• ${classInfo.name()} should not be extended or implemented
• Couldn't find id field of ${classInfo}
• has to be an interface
• should only extend REST Data Panache interface

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/02402b34fcec1d00. Report an issue: GitHub.