Re: [eclipselink-users] Duplicate Entities in GlassFish Persistence Cont

[bht@xxxxxxxxxxxxx]

Hi James,

It was within a single session bean method.

However, the method was annotated with
@TransactionAttribute(value=TransactionAttributeType.NOT_SUPPORTED)

and I overlooked that.
    
Many thanks,

Bernard

On Wed, 2 Mar 2011 07:33:06 -0800 (PST), you wrote:

>
>Within a JTA transaction the EntityManager must always return the same
>instance (unless you call clear).
>
>Are you sure it is a single transaction?  Or is it two different
>transactions, or not in a JTA transaction context?  With a JTA managed
>EntityManager a different instance must be return across each transaction
>boundary.
>
>Ensure you are in a single transaction and are not calling clear, perhaps
>enable logging on finest.
>
>
>bht wrote:
>> 
>> Hi,
>> 
>> I am getting duplicate managed Entities in EntityManager in a single
>> transaction.
>> 
>> This happens only in GlassFish, not with a JUnit test that uses
>> transaction-type="RESOURCE_LOCAL" in persistence.xml.
>> 
>> After retrieveal from an object query, the same entities are looked up
>> again using EntityManager.find().
>> 
>> find() gets the duplicates. I spotted them because they "lost" some
>> transient fields that were set prior to find(), and they have
>> different Object hashcodes.
>> 
>> One could argue that there is no contract that stipulates that
>> EntityManager must return identical entities for the same entity type
>> and ID within the same transaction.
>> 
>> However, there is also no reason for such a waste of memory because if
>> I can compare them, then I have the references to them and they cannot
>> be garbage collected anyway.
>> 
>> Is this a bug? Should I report this?
>> 
>> The scenario is very difficult to deal with - it limits my programming
>> options quite a bit. It is scary and frustrating.
>> 
>> Regards,
>> 
>> Bernard
>> 
>> 
>
>
>-----
>http://wiki.eclipse.org/User:James.sutherland.oracle.com James Sutherland 
>http://www.eclipse.org/eclipselink/
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