Ok, so the short story is that you want to use the @RepositoryRestResource since this creates a HATEOAS service with Spring JPA.
As you can see here adding this annotation and linking it to your Pojo you have a fully functional HATEOAS service without having to implement the repository method or the REST service methods
If you add the @RestController then you have to implement each method that you want to expose on your own and also it does not export this to a HATEOAS format.