Hi Christian,
Well, that's up to the container, but I suppose it would have to query
the properties and save the initial values, then reset back to the
default ones when reassigning. I wouldn't actually recommend doing it,
since EM's are supposed to be lightweight.
-Mike
On 11/05/2012 9:35 AM, Christian Romberg wrote:
> Hi Mike,
>
> How should the app server reinitialize the entity manager instance then?
>
> Regards,
>
> Christian
>
> On Fri, May 11, 2012 at 3:22 PM, michael keith
> <michael.keith_at_oracle.com <mailto:michael.keith_at_oracle.com>> wrote:
>
> Hi Christian,
>
> The clear() method was not intended to reinitialize the EM, but is
> just a method that causes all of the entities in the persistence
> context to be detached. You can actually see an example on page
> 300 that highlights this fact. The footnote you reference was just
> making reference to the fact that a clear() call would need to be
> made on the EM in order for it to be reused. It was not intended
> to be a complete description of how to reuse an EM, or of other
> issues that might also need to be handled. I admit that it could
> be a bit misleading, though...
>
> Regards,
> -Mike
>
>
> On 10/05/2012 9:58 AM, Christian Romberg wrote:
>> Dear group,
>>
>> The spec (2.0) says, p.304, section 7.9.1, footnote 79:
>>
>> "The container may choose to pool EntityManagers: it instead of
>> creating and closing in each case, it may acquire one from its pool
>> and call clear() on it."
>>
>> What should happen with any property settings that were changed
>> by the user?
>> E.g. setFlushMode or any vendor-specific properties?
>>
>> Should clear() also reset them to the values configured for the
>> EntityManagerFactory?
>>
>> I think this would make sense to get a clean, reusable EntityManager.
>>
>> And if this is the common understanding of how clear() should
>> work, I suggest that we add
>> that in the spec.
>>
>> Thank you!
>>
>> Christian
>>
>> --
>> Christian Romberg
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>
>
>
> --
> Christian Romberg
> Chief Engineer| Versant GmbH
> (T) +49 40 60990-0
> (F) +49 40 60990-113
> (E) cromberg_at_versant.com <mailto:cromberg_at_versant.com>
> www.versant.com
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>
> --
> Versant
> GmbH is incorporated in Germany. Company registration number: HRB
> 54723, Amtsgericht Hamburg. Registered Office: Halenreie 42, 22359
> Hamburg, Germany. Geschäftsführer: Bernhard Wöbker, Volker John
>
> CONFIDENTIALITY
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> use of the intended recipient(s) and may contain confidential or
> proprietary information. Any unauthorized review, use, disclosure or
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