This is basically Oscar's preference too, and I can see some merit in it. And if one thinks of @DomainObject as being part of the domain layer only, then it probably should also be renamed to @DomainEntity.
But the other thing to consider is that for each of these annotations we also have a corresponding @XxxLayout. So then the debate was whether to keep things symmetrical. We ended up with three options: option 1 (symmetic, but some duplication): @DomainEntity with @DomainEntityLayout @ViewModel with @ViewModelLayout option 2 (asymmetric): @DomainEntity } with @DomainObjectLayout @ViewModel } option 3 (symmetric, but overloaded): @DomainObject with @DomainObjectLayout (with type=JDO|EXTERNAL|VIEW_MODEL) So far we've had: - one vote for option 1 (Oscar) - four votes for option 3 (Jeroen, Martin, Kevin, Dan) Cheers Dan On 30 December 2014 at 11:07, Ahmed Ragab <ahmed.ra...@netural.com> wrote: > Hi Dan, > > > From your input, I assume a separate @ViewModel annotation is more > consistent due to the fact that the view model is in the application layer > where as @DomainObject is used with entities in the data/domain layer. > > > > > This will also help isolating specifics of both layers in upcoming > versions. > > > ____________________________________________________ > > > > Netural GmbH - Digital Media in Excellence. > > > > > > Ahmed Ragab, M.Sc. | Software Engineer > > > Peter-Behrens-Platz 2, 4020 Linz, Austria > Neustiftgasse 32-34, 1070 Wien, Austria > T +43 (0)732 790903-38, F +43 (0)732 790903-999 > > > ahmed.ra...@netural.com | www.netural.com > > On Tue, Dec 30, 2014 at 1:00 PM, Dan Haywood <d...@haywood-associates.co.uk > > > wrote: > > > Hi Ahmed, > > Thanks for the input. > > On 30 December 2014 at 10:44, Ahmed Ragab <ahmed.ra...@netural.com> > wrote: > >> I guess replacing persistence=JDO with persistence=INTERNAL|MANAGED|ISIS > >> makes more sense with EXTERNAL and VIEW_MODEL since JDO is not the > >> persistence scheme. > >> > >> > > I do quite like all these names, and they make sense if one already > knows a > > bit about Isis, but I'm not sure how grokkable they are for a newbie. > > And, as you then go on to point out... > >> > >> I don't know what persistence=VIEW_MODEL means but looks from the thread > >> comments that it makes sense. However I am still not sure if it could > >> co-exist with JDO/EXTERNAL persistence schemes. > >> > >> > > ... it's because "persistence=VIEW_MODEL" doesn't make sense as a > sentence > > that I was proposing "type" instead: > > That's why I think I still prefer: > > @DomainObject(type=JDO_ENTITY | EXTERNAL_ENTITY | VIEW_MODEL) > > To answer your question about external entity vs view models... > > ... they are both implemented as view models (meaning that their state is > > encoded in their OID, eg as used in its URL in the REST API) > > ... the difference is one of intent: > > ... we would expect that entities to interact with each other (even > if > > one entity is an internally managed JDO entity and the other is > externally > > managed) > > ... we wouldn't expect that an entity can interact with a view model > > (because conceptually the view model is in the application layer, whereas > > the entity is in the domain layer below) > > Thx again > > Dan > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> BR,Ahmed > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> On Tuesday 30 Dec 2014 at 12:14, Dan Haywood < > d...@haywood-associates.co.uk>, > >> wrote: > >> I guess the primary considerations are: > >> > >> - grokkability for new-comers > >> > >> - aesthetics > >> > >> - alignment with DDD terminology. > >> > >> > >> Anyway, thanks for the vote. > >> > >> > >> > >> > >> On 30 December 2014 at 10:01, Kevin Meyer <ke...@kmz.co.za> wrote: > >> > >> > >> > I've been on holiday and only now catching up... > >> > >> > > >> > >> > I vote for 3, but don't have insight to choose between 1 and 2 > >> thereafter. > >> > >> > > >> > >> > > >> > >> > On 29 December 2014 16:11:24 CET, Dan Haywood < > >> > >> > d...@haywood-associates.co.uk> wrote: > >> > >> > >OK, so it comes down to either: > >> > >> > > > >> > >> > > > >> > >> > >*option 1:* > >> > >> > > > >> > >> > >*@DomainEntity(persistence=JDO|EXTERNAL)* > >> > >> > >*@ViewModel* > >> > >> > > > >> > >> > >with > >> > >> > > > >> > >> > >*@DomainEntityLayout* > >> > >> > >*@ViewModelLayout* > >> > >> > > > >> > >> > > > >> > >> > >where: > >> > >> > >* is symmetrical > >> > >> > >* some attributes of @DomainEntity don't apply if > persistence=EXTERNAL > >> > >> > >* the two layouts are basically identical to each other > >> > >> > > > >> > >> > > > >> > >> > >--- or --- > >> > >> > > > >> > >> > >*option 2:* > >> > >> > > > >> > >> > > > >> > >> > >*@DomainEntity(persistence=JDO|EXTERNAL)* > >> > >> > >*@ViewModel* > >> > >> > > > >> > >> > >with > >> > >> > > > >> > >> > >*@DomainObjectLayout* > >> > >> > > > >> > >> > > > >> > >> > >where: > >> > >> > >* not symmetrical > >> > >> > >* some attributes of @DomainEntity don't apply if > persistence=EXTERNAL > >> > >> > > > >> > >> > > > >> > >> > >--- or --- > >> > >> > > > >> > >> > >*option 3:* > >> > >> > > > >> > >> > >*@DomainObject(persistence=JDO|EXTERNAL|VIEW_MODEL)* > >> > >> > > > >> > >> > >with > >> > >> > > > >> > >> > >*@DomainObjectLayout* > >> > >> > > > >> > >> > > > >> > >> > >where: > >> > >> > >* is symmetrical > >> > >> > >* some attributes of @DomainEntity don't apply if > persistence=EXTERNAL > >> > >> > >or > >> > >> > >VIEW_MODEL > >> > >> > >* concept of view model is less visible > >> > >> > > > >> > >> > > > >> > >> > > > >> > >> > >Cast your votes, please! > >> > >> > > > >> > >> > >Dan > >> > >> > > > >> > >> > > > >> > >> > > > >> > >> > >On 29 December 2014 at 15:02, GESCONSULTOR - Óscar Bou < > >> > >> > >o....@gesconsultor.com> wrote: > >> > >> > > > >> > >> > >> > >> > >> > >> > >> > >> > >> As currently there's no "special" support for AggregateRoots or > >> > >> > >> ValueObjects, no more annotations are needed. > >> > >> > >> > >> > >> > >> > >> > >> > >> Sounds like a vote to deprecate. Jeroen has said the same thing. > >> > >> > >Perhaps > >> > >> > >> they should be deleted in v2.0 and reappear, if we want them back, > in > >> > >> > >v3.0. > >> > >> > >> > >> > >> > >> > >> > >> > >> I agree with Jeroen. > >> > >> > >> > >> > >> > >> Currently there's nothing specific about Aggregate Roots on Apache > >> > >> > >Isis, > >> > >> > >> at least on the most used modules, AFAK. > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> * replace @DomainObject(viewModel=false) with > >> > >> > >> @DomainEntity(persistence=JDO) > >> > >> > >> ... this would be the default > >> > >> > >> > >> > >> > >> > >> > >> > >> I like it :) > >> > >> > >> > >> > >> > >> > >> > >> > >> * replace @DomainObject(viewModel=true) with > >> > >> > >> @DomainEntity(persistence=EXTERNAL) > >> > >> > >> > >> > >> > >> > >> > >> > >> This one also! > >> > >> > >> > >> > >> > >> ... for view models representing externally-persisted entities. > In > >> > >> > >the > >> > >> > >> Javadoc, say that auditing, publishing and bounded are not > supported > >> > >> > >for > >> > >> > >> these > >> > >> > >> * keep @ViewModel > >> > >> > >> ... extend to include the non-entity stuff from @DomainObject that > >> > >> > >does > >> > >> > >> apply (basically, I think that's just "objectType" ) > >> > >> > >> ... the intention being that this is used for application-layer > >> > >> > >views. > >> > >> > >> > >> > >> > >> > >> > >> > >> I agree. It should be kept for those use cases. > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> keep @DomainObjectLayout, because everything in it applies equally > to > >> > >> > >both > >> > >> > >> view models (either variety) and JDO entities. > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> Mmmmm.... I would prefer to keep symmetry... I know it introduces > >> > >> > >some > >> > >> > >> redundant checks on implementation but, from the user's > perspective, > >> > >> > >is a > >> > >> > >> clearer model ... > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> I'll reply on your points on @Property and @Parameter separately. > >> > >> > >> > >> > >> > >> Thx > >> > >> > >> Dan > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> Óscar Bou Bou > >> > >> > >> Responsable de Producto > >> > >> > >> Auditor Jefe de Certificación ISO 27001 en BSI > >> > >> > >> CISA, CRISC, APMG ISO 20000, ITIL-F > >> > >> > >> > >> > >> > >> 902 900 231 / 620 267 520 > >> > >> > >> http://www.twitter.com/oscarbou > >> > >> > >> > >> > >> > >> http://es.linkedin.com/in/oscarbou > >> > >> > >> > >> > >> > >> http://www.GesConsultor.com <http://www.gesconsultor.com/> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> Este mensaje y los ficheros anexos son confidenciales. Los mismos > >> > >> > >> contienen información reservada que no puede ser difundida. Si > usted > >> > >> > >ha > >> > >> > >> recibido este correo por error, tenga la amabilidad de eliminarlo > de > >> > >> > >su > >> > >> > >> sistema y avisar al remitente mediante reenvío a su dirección > >> > >> > >electrónica; > >> > >> > >> no deberá copiar el mensaje ni divulgar su contenido a ninguna > >> > >> > >persona. > >> > >> > >> Su dirección de correo electrónico junto a sus datos personales > >> > >> > >constan en > >> > >> > >> un fichero titularidad de Gesdatos Software, S.L. cuya finalidad es > >> > >> > >la de > >> > >> > >> mantener el contacto con Ud. Si quiere saber de qué información > >> > >> > >disponemos > >> > >> > >> de Ud., modificarla, y en su caso, cancelarla, puede hacerlo > enviando > >> > >> > >un > >> > >> > >> escrito al efecto, acompañado de una fotocopia de su D.N.I. a la > >> > >> > >siguiente > >> > >> > >> dirección: Gesdatos Software, S.L. , Paseo de la Castellana, 153 > bajo > >> > >> > >- > >> > >> > >> 28046 (Madrid), y Avda. Cortes Valencianas num. 50, 1ºC - 46015 > >> > >> > >(Valencia). > >> > >> > >> Asimismo, es su responsabilidad comprobar que este mensaje o sus > >> > >> > >archivos > >> > >> > >> adjuntos no contengan virus informáticos, y en caso que los > tuvieran > >> > >> > >> eliminarlos. > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > > >> > >> > -- > >> > >> > Sent from my phone with K-9 Mail. > >> > >> > Please excuse my brevity. > >> >
