That seems fine to me. On 11/27/2017 04:29 PM, Steve Ebersole wrote: > So then how about the following: > > > 1. Add a multi-valued setting to define various categories of JPA > compliance. E.g. `hibernate.jpa.compliance` with multi-selectable values > such as: > 1. query (strict jpql compliance) > 2. txn (transaction handling per spec) > 3. close (multiple calls to EMF and EM #close methods) > 4. list (no bags) > 5. others? > 6. all (there should be some form of specifying all) > 2. Add @Bag as an explicit declaration of a bag, even if > `hibernate.jpa.compliance=list` is specified - that setting just controls > how List with no @OrderColumn is interpreted. I vote to delay adding that > until 6.0 > 3. Retain current behavior for "double close" calls unless "close" > compliance has been specified. > 4. Keep current behavior unless "txn" compliance has been specified > > > > On Mon, Nov 27, 2017 at 4:54 AM andrea boriero <and...@hibernate.org> wrote: > >> On 24 November 2017 at 17:39, Steve Ebersole <st...@hibernate.org> wrote: >> >>> Andrea, SF is a EMF. Unwrapping simply returns the same instance. >>> >> yes but has you pointed out due to the bootstrapping the behaviour of the >> SF will be strict JPA compliant. >> >>> Another thing I was discussing with Andrea in chat is possibly making >>> these multi-valued, or having multiple values for this. I can't imagine >>> the FQN case is really all that appealing to a user. I'm fairly certain a >>> user would rather simply say "yeah, treat transactions according the JPA >>> spec" as opposed to "here is a class I will provide that will tell will >>> treat transactions according to the JPA spec". >>> >>> We have started to identify some cases where we deviate from the spec[1], >>> such as: >>> * Strict query compliance. As I mentioned earlier we do have such a >>> setting already for this in particular >>> * List versus Bag determination from mappings. >>> * Closed EMF (SF) handling >>> * EntityTransaction status checking - JPA says we should throw exceptions >>> whereas we just ignore the call. >>> >>> We need to decide also which of these we want to just change outright >>> versus controlling via a setting. >>> >>> * Setting >>> * Setting, or introduce a new @Bag annotation - the annotation option is >>> actually pretty appealing since often times the bag behavior is so >>> unexpected from users... >>> >> @Bag seems really a good idea to me but that means changing the current >> default behaviour, forcing users to change the code, so not sure if we need >> also a setting. >> >> >>> * I think we should just change the behavior of calling EMF#close on a >>> closed EMF. Any application that happens to be relying on us no-op'ing >>> this call can easily change that to protect the call with an `#isOpen` >>> check. In fact I think we should change all of these to match the JPA >>> expectations such that it is an error to call any of the following: #close, >>> #getCache, #getMetamodel, #getCriteriaBuilder, #getProperties, >>> #getPersistenceUnitUtil, #createEntityManager. To me these all seem pretty >>> reasonable. And in fact I think we used to handle this all properly from >>> the EMF side. I think we just lost that behavior when we changed to have >>> our contracts extend the JPA ones since we kept the legacy Hibernate >>> behavior in SessionFactory. >>> >> I do not like the EMF#close behaviour, probably a prefer a separate >> setting for this. >> >> >>> * This one I am very undecided. I can see very valid arguments for each. >>> >> probably for such case a setting may be a good option. >> >>> [1] we really ought to start keeping a list of these. I have started >>> adding them to the migration guide. Just as a list of things we need to >>> support configuring or switch to the JPA "way". >>> >>> On Fri, Nov 17, 2017 at 11:06 AM andrea boriero <and...@hibernate.org> >>> wrote: >>> >>>> I think for 5.3 it's still fine to rely on isJpaBootstrap may be >>>> documenting that a SF obtained from unwrapping an EMF will conform to the >>>> JPA spec in term of exceptions. >>>> >>>> On 16 November 2017 at 21:09, Vlad Mihalcea <mihalcea.v...@gmail.com> >>>> wrote: >>>> >>>>> When I said multiple modes, I was thinking of defining all these >>>>> situations >>>>> In some interface which declares methods like: >>>>> >>>>> boolean throwsExceptionWhenClosingAClosedEMF() >>>>> >>>>> The interface can have two implementations for Strict JPA and Native >>>>> mode. >>>>> >>>>> However, the setting could take the FQN of the interface >>>>> implementation, so >>>>> a user can define those compatibility methods according to their needs. >>>>> >>>>> E.g. Maybe someone wants the Strict JPA mode but with just 2 >>>>> differences; >>>>> >>>>> - don't throw exception when closing the ENG twice >>>>> - use the native Hibernate FlushMode.AUTO instead of the JPA one. >>>>> >>>>> Vlad >>>>> >>>>> On 16 Nov 2017 10:49 pm, "Steve Ebersole" <st...@hibernate.org> wrote: >>>>> >>>>>> There is already a similar setting, although specific to query >>>>> language: >>>>>> `hibernate.query.jpaql_strict_compliance` - so there is precedence for >>>>>> such a solution. >>>>>> >>>>>> I'm not sure about the "with multiple modes" aspect though. What are >>>>>> these other enumerated mode values? >>>>>> >>>>>> >>>>>> On Thu, Nov 16, 2017 at 2:15 PM Vlad Mihalcea < >>>>> mihalcea.v...@gmail.com> >>>>>> wrote: >>>>>> >>>>>>> Where the JPA way is questionable, let's add one configuration: >>>>>>> hibernate.jpa.compliance with multiple modes: >>>>>>> >>>>>>> - strict: we do whatever the JPA standard says we should do, like >>>>>>> throwing an exception when trying to close the EMF twice >>>>>>> - native: we bend the rule where we don't agree with the standard >>>>>>> >>>>>>> Maybe we should expose all those cases and group them in some >>>>> interface >>>>>>> to allow the user to customize the level of compliance they need. >>>>>>> >>>>>>> Vlad >>>>>>> >>>>>>> On Thu, Nov 16, 2017 at 10:06 PM, Steve Ebersole < >>>>> st...@hibernate.org> >>>>>>> wrote: >>>>>>> >>>>>>>> It was added deprecated. Meaning I added it knowing it would go >>>>> away >>>>>>>> and I wanted to avoid users using it. >>>>>>>> >>>>>>>> BTW, I am talking about a 5.3 release specifically covering 5.2 + >>>>> JPA >>>>>>>> 2.2. Yes there is a longer term aspect as well with 6.0 and beyond. >>>>>>>> >>>>>>>> Its specifically the "where the JPA way is questionable" aspect I am >>>>>>>> asking about. Like to me, it really never makes sense to throw an >>>>>>>> exception when I close something that is already closed. So how do >>>>> we >>>>>>>> handle cases like this? >>>>>>>> >>>>>>>> >>>>>>>> On Thu, Nov 16, 2017 at 1:51 PM Vlad Mihalcea < >>>>> mihalcea.v...@gmail.com> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> Hi Steve, >>>>>>>>> >>>>>>>>> I think that for 5.2 was ok to have the isJpaBootstrap method to >>>>> avoid >>>>>>>>> breaking compatibility for the native bootstrap. >>>>>>>>> For 6.0, maybe it's easier if we just align to the JPA spec where >>>>> it >>>>>>>>> makes sense, >>>>>>>>> and only provide a separation where the JPA way is questionable. >>>>>>>>> >>>>>>>>> I noticed that the isJpaBootstrap method is deprecated. Was it >>>>>>>>> intended to be removed in 6.0? >>>>>>>>> >>>>>>>>> Vlad >>>>>>>>> >>>>>>>>> On Thu, Nov 16, 2017 at 6:21 PM, Steve Ebersole < >>>>> st...@hibernate.org> >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Part of 5.2 was merging the JPA contracts into the corresponding >>>>>>>>>> Hibernate >>>>>>>>>> ones. So, e.g., we no longer "wrap" a SessionFactory in an impl >>>>> of >>>>>>>>>> EntityManagerFactory - instead, SessionFactory now extends >>>>>>>>>> EntityManagerFactory. >>>>>>>>>> >>>>>>>>>> This caused a few problems that we handled as they came up. In >>>>>>>>>> working on >>>>>>>>>> the JPA 2.2 compatibility testing, I see that there are a few more >>>>>>>>>> still >>>>>>>>>> that we need to resolve. Mostly they relate to JPA expecting >>>>>>>>>> exceptions in >>>>>>>>>> certain cases where Hibernate has historically been lenient. >>>>> E.g., JPA >>>>>>>>>> says that calling EntityManagerFactory#close on an EMF that is >>>>> already >>>>>>>>>> closed should result in an exception. Historically, calling >>>>>>>>>> SessionFactory#close on a SF that is already closed is simply >>>>> ignored. >>>>>>>>>> Philosophical debates aside[1], we need to decide how we want to >>>>> handle >>>>>>>>>> this situation such that we can throw the JPA-expected exceptions >>>>> when >>>>>>>>>> needed. Do we simply change SF#close to match the JPA >>>>> expectation? >>>>>>>>>> Or do >>>>>>>>>> we somehow >>>>>>>>>> make SF#close aware of JPA versus "native" use? This latter >>>>> option >>>>>>>>>> was the >>>>>>>>>> intent of `SessionFactoryOptions#isJpaBootstrap` and we can >>>>> certainly >>>>>>>>>> continue to use that as the basis of the solution here for other >>>>> cases. >>>>>>>>>> This `#isJpaBootstrap` flag is controlled by the JPA bootstrap >>>>> code. >>>>>>>>>> So if >>>>>>>>>> the EMF is created in either of the 2 JPA-defined bootstrap >>>>> mechanisms, >>>>>>>>>> that flag is set to true. It's an ok solution, but it does have >>>>> some >>>>>>>>>> limitations - mainly, there was previously a distinction between >>>>>>>>>> SF#close >>>>>>>>>> being called versus EMF#close being called (they were different >>>>>>>>>> classes, so >>>>>>>>>> they could react differently). Therefore, regardless of bootstrap >>>>>>>>>> mechanism, if the user unwrapped the EMF to a SF, they would >>>>> always >>>>>>>>>> get the >>>>>>>>>> legacy SF behavior. >>>>>>>>>> >>>>>>>>>> So long story short, so we want to consider an alternative >>>>> approach to >>>>>>>>>> deciding what to do in "some"[2] of these cases? Again, we >>>>> clearly >>>>>>>>>> need >>>>>>>>>> these to throw the spec-mandated exceptions in certain "strict >>>>>>>>>> compliance" >>>>>>>>>> situations. The question really is how to do that. Should we: >>>>>>>>>> >>>>>>>>>> 1. just completely change the behavior to align with the spec? >>>>>>>>>> 2. change the behavior to match the spec *conditionally*, >>>>> where that >>>>>>>>>> condition could be: >>>>>>>>>> 1. `#isJpaBootstrap` >>>>>>>>>> 2. some setting >>>>>>>>>> 3. some extension contract >>>>>>>>>> 4. something else? >>>>>>>>> >>>>>>>>>> Thoughts? >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> [1] It's not relevant e.g. that I think JPA is wrong here. We >>>>> need to >>>>>>>>>> comply with the spec, at least in certain cases ;) >>>>>>>>>> >>>>>>>>>> [2] I say "some" here, because I think the spec is correct in some >>>>>>>>>> cases - >>>>>>>>>> for example, I think its clearly correct that a closed EMF throws >>>>> an >>>>>>>>>> exception when `#createEntityManager` is called. Personally I >>>>> think >>>>>>>>>> its >>>>>>>>>> questionable whether closing an already closed EMF should be an >>>>>>>>>> exception. >>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>>> hibernate-dev mailing list >>>>>>>>>> hibernate-dev@lists.jboss.org >>>>>>>>>> https://lists.jboss.org/mailman/listinfo/hibernate-dev >>>>>>>>>> >>>>>>>>> >>>>> _______________________________________________ >>>>> hibernate-dev mailing list >>>>> hibernate-dev@lists.jboss.org >>>>> https://lists.jboss.org/mailman/listinfo/hibernate-dev >>>>> >>>> > _______________________________________________ > hibernate-dev mailing list > hibernate-dev@lists.jboss.org > https://lists.jboss.org/mailman/listinfo/hibernate-dev
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