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 <[email protected]> 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 <[email protected]> > 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 > [email protected] > > Yahoo Messenger / Skype: hansamann > Personal Homepage, Wiki & Blog: http://www.svenhaiges.de > > Subscribe to the Grails Podcast: > http://www.grailspodcast.com > -- Sven Haiges [email protected] Yahoo Messenger / Skype: hansamann Personal Homepage, Wiki & Blog: http://www.svenhaiges.de Subscribe to the Grails Podcast: http://www.grailspodcast.com --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en -~----------~----~----~----~------~----~------~--~---
