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Re: [eclipselink-users] re move() and a OneToMany mapping with CascadeType.PERSIST
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I can't see anything wrong with the clear() method it uses an iterator to
remove all elements in the delegate. The delegate should be empty after the
clear. Are you seeing the delegate still having objects in it?
patric-7 wrote:
>
>> Calling clear() on the set should cause it to be removed as you will no
>> longer have a reference to the removed object.
>
> Please have a look at IndirectSet.clear() in the source.
> In my case, the delegate's clear() will not be invoked, so the
> references are still there.
> This causes that the non-empty Set will be traversed on commit when
> changing the Set's parent hence undeleting the scheduled-for-removal
> entities.
>
>
> Zitat von James Sutherland <jamesssss@xxxxxxxxx>:
>
>>
>> Calling clear() on the set should cause it to be removed as you will no
>> longer have a reference to the removed object. Do you have a reference
>> from
>> another object?
>>
>> I can't see how B could get re-persisted if you clear the reference to it
>> from A. Are you sure there is no reference to be? Perhaps put a
>> break-point in a prePersist event in B and check what is causing it to be
>> persisted.
>>
>>
>>
>> patric-7 wrote:
>>>
>>> I have no problem removing all references to an entity which has to be
>>> removed.
>>> What I am trying to point out is that EclipseLink behaves strangely in
>>> a special case:
>>>
>>> It makes a difference for EclipseLink if I remove the reference(s) by
>>> setting the OneToMany-IndirectSet to null (this will work) or if I
>>> call clear() on the IndirectSet (which won't work in case of the
>>> cascade types exactly set to CascadeType.PERSIST, CascadeType.MERGE).
>>>
>>>
>>> Zitat von James Sutherland <jamesssss@xxxxxxxxx>:
>>>
>>>>
>>>> Before you remove and object you must ensure that you remove all
>>>> references
>>>> to it. Otherwise you are corrupting your object model. Normally you
>>>> would
>>>> get a constraint error if you tried to delete something that had
>>>> references,
>>>> but it depends on the constraint direction.
>>>>
>>>> Before removing B you must remove it from A's collection of Bs (and all
>>>> other object that reference B).
>>>>
>>>> The cascade persist in JPA is required by the JPA spec to re-persist
>>>> removed
>>>> objects (odd but true). But not removing the reference to your removed
>>>> object is wrong and will corrupt your object model irregardless of the
>>>> JPA
>>>> issue, so you need to remove its references.
>>>>
>>>> If you removed the cascade persist, the object would not get
>>>> re-persisted
>>>> (but you object would still be corrupt).
>>>>
>>>> EclipseLink does provide some persistence unit properties that control
>>>> this
>>>> behavior,
>>>> "eclipselink.persistence-context.persist-on-commit"="false" - will
>>>> avoid
>>>> the
>>>> auto persist on commit
>>>> "eclipselink.persistence-context.commit-without-persist-rules"="true" -
>>>> may
>>>> resolve the issue
>>>>
>>>>
>>>> patric-7 wrote:
>>>>>
>>>>> Your proposed workaround leads to the expected behavior - the entries
>>>>> are
>>>>> now
>>>>> being removed.
>>>>>
>>>>> Should I open a bug report?
>>>>>
>>>>> Thank you and best regards,
>>>>> Patric
>>>>>
>>>>> Am 28.01.2011 19:02, schrieb Rohit Banga:
>>>>>> In case 1, can you try the following:
>>>>>>
>>>>>>
>>>>>> // initially a.getBs() will be a set containing one value
>>>>>> em.remove(B);
>>>>>> a.setAttr(somevalue);
>>>>>> a.setBs(null);
>>>>>>
>>>>>> In this case I think B should be removed.
>>>>>> Can you please try this and post the behavior you observe?
>>>>>>
>>>>>> Member Technical Staff
>>>>>> Oracle India Private Limited
>>>>>> 91 80 41085685
>>>>>>
>>>>>> ----- Original Message -----
>>>>>> From: patric@xxxxxxxxxxx
>>>>>> To: eclipselink-users@xxxxxxxxxxx
>>>>>> Sent: Friday, January 28, 2011 7:28:02 PM GMT +05:30 Chennai,
>>>>>> Kolkata,
>>>>>> Mumbai, New Delhi
>>>>>> Subject: Re: [eclipselink-users] remove() and a OneToMany mapping
>>>>>> with
>>>>>> CascadeType.PERSIST
>>>>>>
>>>>>> I'd like to add some additional information:
>>>>>>
>>>>>> When adding the CascadeType.REFRESH to the OneToMany mapping,
>>>>>> the described "behavior" cannot be seen anymore:
>>>>>>
>>>>>> @OneToMany(mappedBy="gtrAnnTaxStmt_",
>>>>>> cascade = { CascadeType.PERSIST, CascadeType.MERGE,
>>>>>> CascadeType.REFRESH })
>>>>>> private Set bSet_;
>>>>>>
>>>>>>
>>>>>> Best regards,
>>>>>> Patric
>>>>>>
>>>>>> Zitat von patric@xxxxxxxxxxx:
>>>>>>
>>>>>>> Hello everyone,
>>>>>>>
>>>>>>> I have a question regarding the importance of a remove() against a
>>>>>>> cascade persist mapping.
>>>>>>>
>>>>>>> Imagine a simple parent-child situation reflecting an 1:N
>>>>>>> cardinality:
>>>>>>>
>>>>>>> Entity class A is the parent, entity class B the child.
>>>>>>> A defines a OneToMany mapping to B:
>>>>>>>
>>>>>>> @OneToMany(mappedBy="a_",
>>>>>>> cascade={CascadeType.PERSIST, CascadeType.MERGE} )
>>>>>>> private Set bSet_;
>>>>>>>
>>>>>>>
>>>>>>> In the following example one A instance references to exactly one B
>>>>>>> instance.
>>>>>>> Both are already persisted to the database and will be read after
>>>>>>> the begin of the transaction.
>>>>>>>
>>>>>>> Case #1:
>>>>>>> When calling em.remove(B) and changing A followed by a commit, some
>>>>>>> strange behavior can be seen:
>>>>>>>
>>>>>>> B will not be removed.
>>>>>>> It seems that the change to A causes that cascade persist will cause
>>>>>>> a silent 'undeletion' of B.
>>>>>>> (which happens during changeset calculation on commit)
>>>>>>>
>>>>>>> Case #2:
>>>>>>> When not changing A everything works expected and B will be removed.
>>>>>>>
>>>>>>>
>>>>>>> My questions:
>>>>>>>
>>>>>>> 1. Are both cases intentional behavior?
>>>>>>> I would expect that the explicit remove() should override the
>>>>>>> implicit cascade persist in either cases.
>>>>>>>
>>>>>>> 2. Is there a a workaround that a remove() will be respect with
>>>>>>> higher priority(beside removing the cascade on the mapping)?
>>>>>>>
>>>>>>> Thank you and best regards,
>>>>>>> Patric
>>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>> -----
>>>> http://wiki.eclipse.org/User:James.sutherland.oracle.com James
>>>> Sutherland
>>>> http://www.eclipse.org/eclipselink/
>>>> EclipseLink , http://www.oracle.com/technology/products/ias/toplink/
>>>> TopLink
>>>> Wiki: http://wiki.eclipse.org/EclipseLink EclipseLink ,
>>>> http://wiki.oracle.com/page/TopLink TopLink
>>>> Forums: http://forums.oracle.com/forums/forum.jspa?forumID=48 TopLink
>>>> ,
>>>> http://www.nabble.com/EclipseLink-f26430.html EclipseLink
>>>> Book: http://en.wikibooks.org/wiki/Java_Persistence Java Persistence
>>>> Blog: http://java-persistence-performance.blogspot.com/ Java
>>>> Persistence
>>>> Performance
>>>> --
>>>> View this message in context:
>>>> http://old.nabble.com/remove%28%29-and-a-OneToMany-mapping-with-CascadeType.PERSIST-tp30785713p30827278.html
>>>> Sent from the EclipseLink - Users mailing list archive at Nabble.com.
>>>>
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>>>
>>>
>>>
>>>
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>>
>>
>> -----
>> http://wiki.eclipse.org/User:James.sutherland.oracle.com James Sutherland
>> http://www.eclipse.org/eclipselink/
>> EclipseLink , http://www.oracle.com/technology/products/ias/toplink/
>> TopLink
>> Wiki: http://wiki.eclipse.org/EclipseLink EclipseLink ,
>> http://wiki.oracle.com/page/TopLink TopLink
>> Forums: http://forums.oracle.com/forums/forum.jspa?forumID=48 TopLink ,
>> http://www.nabble.com/EclipseLink-f26430.html EclipseLink
>> Book: http://en.wikibooks.org/wiki/Java_Persistence Java Persistence
>> Blog: http://java-persistence-performance.blogspot.com/ Java Persistence
>> Performance
>> --
>> View this message in context:
>> http://old.nabble.com/remove%28%29-and-a-OneToMany-mapping-with-CascadeType.PERSIST-tp30785713p30827819.html
>> Sent from the EclipseLink - Users mailing list archive at Nabble.com.
>>
>> _______________________________________________
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>> https://dev.eclipse.org/mailman/listinfo/eclipselink-users
>>
>
>
>
>
> _______________________________________________
> eclipselink-users mailing list
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> https://dev.eclipse.org/mailman/listinfo/eclipselink-users
>
>
-----
http://wiki.eclipse.org/User:James.sutherland.oracle.com James Sutherland
http://www.eclipse.org/eclipselink/
EclipseLink , http://www.oracle.com/technology/products/ias/toplink/
TopLink
Wiki: http://wiki.eclipse.org/EclipseLink EclipseLink ,
http://wiki.oracle.com/page/TopLink TopLink
Forums: http://forums.oracle.com/forums/forum.jspa?forumID=48 TopLink ,
http://www.nabble.com/EclipseLink-f26430.html EclipseLink
Book: http://en.wikibooks.org/wiki/Java_Persistence Java Persistence
Blog: http://java-persistence-performance.blogspot.com/ Java Persistence
Performance
--
View this message in context: http://old.nabble.com/remove%28%29-and-a-OneToMany-mapping-with-CascadeType.PERSIST-tp30785713p30884142.html
Sent from the EclipseLink - Users mailing list archive at Nabble.com.
