Related: why are child objects not automatically detached if the
parent is detached? Would that not not logical?
Cheers
Sven
On Fri, Sep 11, 2009 at 12:51 PM, Sven Haiges
<sven.hai...@googlemail.com> wrote:
> Andy, first of all thx for the response. Things begin to make a little
> more sense.
>
> But still how do I solve my specific issue then. Is the solution to
> access the retweets field within the JPA callback in this case (as
> outside it counts as a 'commit' ??
>
> This is the groovy / grails code used in this case. I could try to
> access the retweets at XXX and then save the result in another,
> transient field... but this is really ugly.
>
> def tweetInstanceList =[]
> 38 jpaTemplate.execute( { entityManager ->
> 39 def query = entityManager.createQuery("select tweet
> from org.groovytweets.Tweet tweet order by tweet.statusId desc")
> 40 query.maxResults = 50
> 41 tweetInstanceList = query.resultList
> XXX
> 42 } as JpaCallback )
>
>
> ---
>
> So detaching retweets seems like the best. But how? If you are saying
> JPA1 does not allow this, it means there is no way for me to make this
> nice?
>
> Cheers
> Sven
>
> On Fri, Sep 11, 2009 at 12:43 PM, datanucleus <andy_jeffer...@yahoo.com>
> wrote:
>>
>>> I am not sure what you mean. I never detach anything explicitly, so I
>>> have no idea how to detach anything else.
>>
>> Yes you do ... in JPA at commit or at close of the EntityManager the
>> contract is to detach all current entities, as per the JPA spec. As
>> you identified later in your post.
>>
>>> >javax.jdo.JDODetachedFieldAccessException: You have just attempted to
>>> access field "retweets" yet this field was not detached when you
>>> detached the object. Either dont access this field, or detach it when
>>> detaching the object.
>>>
>>> I find that very strange.
>>> 1. I am using JPA, how do I get a JDO exception?
>>
>> Because the JPA spec doesn't define the behaviour of accessing an
>> undetached field of a detached object so we can throw whatever we
>> want. We could throw something DataNucleus specific but then what's
>> the point ? In some implementations they do nothing and return null,
>> so the user has no real expectation here. Symptoms of a poor spec ...
>>
>>
>> JPA2 will provide a detach method, when the spec is final ...
>>
>> --Andy (DataNucleus)
>> >>
>>
>
>
>
> --
> Sven Haiges
> sven.hai...@googlemail.com
>
> Yahoo Messenger / Skype: hansamann
> Personal Homepage, Wiki & Blog: http://www.svenhaiges.de
>
> Subscribe to the Grails Podcast:
> http://www.grailspodcast.com
>
--
Sven Haiges
sven.hai...@googlemail.com
Yahoo Messenger / Skype: hansamann
Personal Homepage, Wiki & Blog: http://www.svenhaiges.de
Subscribe to the Grails Podcast:
http://www.grailspodcast.com
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