Custom implementation of CrudRepository.save() not called if generics not declared exactly (reopener) [DATACMNS-1225]

Sebastian J opened DATACMNS-1225 and commented

This is a reopener to DATACMNS-1008 (unsure if the old one should be reopened or a new ticket should be created).

The issue is still the same and can be reproduced with these classes:

public interface FooRepository extends CrudRepository<Foo, Long>, FooRepositoryCustom {
	// Workaround as per DATACMNS-1008 still works
	//<X extends Foo> X save(X foo);
}

public interface FooRepositoryCustom {
	Foo doNonstandardThing(Foo foo);
}

public class FooRepositoryImpl implements FooRepositoryCustom {
	
    public Foo save(Foo foo) {
        // Do things
    	return foo;
    }
}

@Service
public class FooService {
    private final FooRepository fooRepo;
    
    @Autowired
    public FooService(FooRepository fooRepo) {
        this.fooRepo = fooRepo;
    }

    public void processFoo(Foo foo) {
    	fooRepo.doNonstandardThing(foo);
        fooRepo.save(foo);
    }
}

As previously, the save method in the custom implementation is never called.

From debugging it looks to me that the error occurs here: org.springframework.data.repository.core.support.RepositoryComposition.RepositoryFragments.invoke(Method, Object[]) as ReflectionUtils.findMethod in org.springframework.data.repository.core.support.RepositoryFragment.hasMethod(Method) will never find the custom method.
It is looking for a method save(Object) method (due to the generic erasure) but the custom method's parameter is of type Foo

Affects: 2.0.1 (Kay SR1), 2.0.2 (Kay SR2)

Reference URL: https://github.com/derjust/spring-data-dynamodb/tree/issue_77/src/test/java/org/socialsignin/spring/data/dynamodb/issue77

Issue Links:

• DATACMNS-1008 Custom implementation of CrudRepository.save(…) not called if generics not declared exactly