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From Jean-Baptiste BRIAUD -- Novlog <j-b.bri...@novlog.com>
Subject Re: Custom proxy : idea review needed
Date Tue, 04 Aug 2009 12:41:57 GMT
it is still failling !
After detaching and even closing the entity manager, accessing a not  
retreived field using fetch plan cause a NPE in pcReplaceField ...

I'm completly blocked and in the dark ... I even don't see where  
investigating more now ...

Any idea ?



On Aug 4, 2009, at 11:51 , Jean-Baptiste BRIAUD -- Novlog wrote:

>
> On Aug 4, 2009, at 03:06 , Michael Dick wrote:
>
>>
>> Hi,
>>
>> Have you tried detaching your entities? When an entity is detached  
>> OpenJPA
>> won't go to the database to load a field. So we'll return null for  
>> anything
>> that isn't in your fetch group (exception : if you load the field  
>> prior to
>> detaching then it will be available).
> This is a good point and it had worked, but I'm puzzled : I thought  
> closing the entityManager will detach managed entities ... and  
> apparently it is not the case.
> If I want to detach entity, I have to detach it explicitly, I didn't  
> spot that.
>>
>> You can detach by calling EntityManager.clear() or
>> OpenJPAEntityManager.detach(Object o). Either way it'll be a lot  
>> easier than
>> creating your own proxy class.
> Sure, it is a *lot* more easier :-)
> I'm using detachAll to detach a full collection at once.
> I'm not sure about the behavior of clear(), should clear all managed  
> entity ?
>
> By the way, this detach behavior will be ammended in version 2.x, I  
> might try this version, but I feel it could be risky ... On the  
> other hand, my project's time frame fit well with this version 2.
> Any feedback on 2.0 relliability ?
>
>>
>> Hope this helps,
> It solve the problem, big big thanks !
>> -mike
>>
>>
>> Jean-Baptiste BRIAUD -- Novlog wrote:
>>>
>>> Hi,
>>>
>>> My question is "is there simpler things to do ?"
>>> Please, review that idea and don't hesitate to comment ...
>>>
>>> Step 1 : I want partial object, not hashtables. It could be a Person
>>> with only some attributes having values.
>>> this concern not only @Basic attribute but also any relational
>>> attributes like @ManyToOne, ...
>>> => I used fetch plan and it works fine.
>>>
>>> Step 2 : I'm using an Apache lib via a third party framework that
>>> explore all accessors (beanutils).
>>> Unfortunatly, unretreived attributes came with a proxy.
>>> As a consequence, all unreitreived attributes are now retreived
>>> wasting all the benefit of having used fetch plan ...
>>>
>>> Step 3 : I first try to get rid of that proxies but without success,
>>> so I though I could just have my own proxy that could subclass the
>>> OpenJPA default proxy
>>> and just ensure in my subclass that when I need no proxy, the  
>>> default
>>> behavior is bypassed.
>>>
>>> What do you think about that idea ?
>>>
>>>
>>
>> -- 
>> View this message in context: http://n2.nabble.com/Custom-proxy-%3A-idea-review-needed-tp3376839p3381672.html
>> Sent from the OpenJPA Users mailing list archive at Nabble.com.
>>
>
>


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