Markus Fuchs wrote:
> Hi Greg,
>
> Do you get a foreign key violation w/o using @PreRemove callbacks in
> your pojos? Are you using a current glassfish build?
>
Hi Markus,
Yes. When I em.remove() an ArticlePlacement without the @PreRemove, I
get a PSQLException (I'm using PostgreSQL) with a foreign key constraint
violation message.
I'm using v2b50.
Thanks for the reply.
Cheers,
Greg
> Thanks,
>
> -- markus.
>
> Greg Ederer wrote:
>> I managed to get this working by adding the following to Article:
>>
>> @PreRemove
>> public void beforeRemove()
>> {
>> List<ArticlePlacement> articlePlacements = getArticlePlacements();
>> for(ArticlePlacement ap : articlePlacements)
>> {
>> ap.setArticle(null);
>> }
>> }
>>
>> And in ArticlePlacement:
>>
>> @PreRemove
>> public void beforeRemove()
>> {
>> getArticleGroup().removeArticlePlacement(this);
>> if(getArticle() != null)
>> {
>> getArticle().removeArticlePlacement(this);
>> }
>> }
>>
>> I have a feeling this is not the best way to handle this (and, I'm
>> guessing that I'll feel like a dummy when I find out the correct way
>> to do this, because it will be pretty obvious).
>>
>> Any advice welcome.
>>
>> Cheers,
>>
>> Greg
>>
>> Greg Ederer wrote:
>>> Oops! Accidentally hit send. Please ignore previous post.
>>>
>>> I have a model containing three entity classes: Article,
>>> ArticleGroup and ArticlePlacement. An ArticleGroup contains zero or
>>> more ArticlePlacement objects. Each ArticlePlacement wraps an
>>> Article (ArticlePlacement also has a start run date and an end run
>>> date, which allows me to run an article in multiple groups during
>>> different periods).
>>>
>>> So, in Article, I have:
>>>
>>> @OneToMany(mappedBy = "article", cascade=CascadeType.ALL)
>>> private List<ArticlePlacement> articlePlacements = new
>>> ArrayList<ArticlePlacement>();
>>>
>>> In ArticleGroup, I have:
>>>
>>> @OneToMany(cascade={CascadeType.PERSIST, CascadeType.MERGE,
>>> CascadeType.REFRESH})
>>> @OrderBy("position ASC")
>>> private List<ArticlePlacement> articlePlacements = new
>>> ArrayList<ArticlePlacement>();
>>>
>>> And, in ArticlePlacement, I have:
>>>
>>> @ManyToOne
>>> private Article article;
>>>
>>> @ManyToOne
>>> private ArticleGroup articleGroup;
>>>
>>> @PreRemove
>>> public void beforeRemove()
>>> {
>>> getArticleGroup().removeArticlePlacement(this);
>>> getArticle().removeArticlePlacement(this);
>>> }
>>>
>>> When I EntityManager.remove() an Article, I get a
>>> java.util.ConcurrentModificationException due to the
>>> getArticle().removeArticlePlacement(this) in @PreRemove, above.
>>> But, if I comment this out, I get a "violates foreign key"
>>> PSQLException.
>>>
>>> Can someone tell me how to deal with this situation correctly?
>>>
>>> Thanks!
>>>
>>> Greg
>>>
>>
>>
--
| E R G O N O S I S
| Greg Ederer
| Lead Developer
| greg_at_ergonosis.com
| 360.774.6848
|