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https://issues.apache.org/jira/browse/OPENJPA-258?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Albert Lee updated OPENJPA-258:
-------------------------------

    Fix Version/s:     (was: 1.0.1)
                   1.0.2

Defer to next release.

> MetaDataInheritanceComparator is not transitive; C > B > A > C leads to 
> out-of-memory crash in PCEnhancer
> ---------------------------------------------------------------------------------------------------------
>
>                 Key: OPENJPA-258
>                 URL: https://issues.apache.org/jira/browse/OPENJPA-258
>             Project: OpenJPA
>          Issue Type: Bug
>          Components: jpa
>    Affects Versions: 0.9.6
>         Environment: Sun JDK 5, Sun JDK 6
>            Reporter: Jonathan Feinberg
>            Priority: Blocker
>             Fix For: 1.0.2
>
>         Attachments: jpa-comparator-bug.zip
>
>
> Comparisons done by MetaDataInheritanceComparator are not transitive. It is 
> possible to have classes A, B, and C such that the comparator simultaneously 
> reports that A > B, B > C, and C > A. Under certain unlucky conditions, this 
> causes the SortedTree holding the metadata resolution buffer to become 
> confused during Red-Black fix, such that it can retrieve a certain element, 
> but not delete it. The "processed" list then grows until heap is exhausted.
> In the enclosed sample project, 
> A < B by name
> B < C by assignable primary key field
> C < A by "levels" from base class (Object)
> If you import the enclosed eclipse project into an AspectJ-enabled eclipse, 
> and refer the AspectJ compiler to an OpenJPA jar file, you'll get the 
> following output:
>   bug.B > bug.A
>   bug.C > bug.B
>   bug.A > bug.C
>   Cycle detected: 
>   bug.A > bug.C > bug.B > bug.A
> The project will work outside of AspectJ, and will exhibit the out of memory 
> condition described above.
> I acknowledge that the enclosed persistence.xml file is not kosher, in that 
> it doesn't list all classes to be instrumented. My own project, affected by 
> this bug, has a correct persistence.xml file. I had to work hard to contrive 
> a simple example, as the order in which classes are buffered affects the 
> appearance of the bug.
> There is no work-around that I know of. I don't believe that the comparator's 
> semantics are well-defined.

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