Re: [eclipselink-users] Creation of M-M-Relation/Association fails

[Tom Ware <tom.ware@xxxxxxxxxx>]

Hi Michael,

  A few more questions.

1. What do line.removeCompatibleProducts (obsoletes) and 
line.addCompatibleProducts (news) do?

2. Is it possible that obsoletes and news contain the same data?

3. Is it possible to get a sample output with logging set to FINEST?

-Tom

Michael Simons wrote:
> Hello Tom,
>
> As the code runs within a standalone application, the entity manager is created
> (emf.createEntityManager()) at the start and closed when the app terminates.
> I get the transaction using em.getTransaction()
> The code that persists the entities is attached (excerpt.java)
>
> Kind Regards, Michael
>
> Tom Ware schrieb:
> > Hi Michael,
> >
> >   What is the actual code you are running?  (i.e. how do you get your
> > entity manager, what does the code that persists your objects look
> > like?  how are you getting your transactions?)
> >
> > -Tom
> >
> > Michael Simons wrote:
> > > Hello,
> > >
> > > I've got an Entity class Product with a self-relation:
> > >     /** Set of products this one is compatible with.*/
> > >     @ManyToMany(fetch=FetchType.LAZY, cascade={CascadeType.PERSIST,
> > > CascadeType.REFRESH})
> > >     @JoinTable(name="product_product_compatibility",
> > >         joinColumns={@JoinColumn(name="prev_product_id")},
> > >         inverseJoinColumns={@JoinColumn(name="next_product_id")})
> > >     private Set<Product> compatibleProducts = new HashSet<Product>();
> > >
> > > Guess what happens when I add products to this set like this:
> > >     public boolean addCompatibleProduct (Product product) {
> > >         if (compatibleProducts == null)
> > >             compatibleProducts = new HashSet<Product>();
> > >         boolean added = compatibleProducts.add (product);
> > >         if (added)
> > >             product.addCompatibleProduct (this);
> > >         return added;
> > >     }
> > >
> > > If you said nothing, you've won. The only SQL that was generated is:
> > > [EL Fine]: 2010-03-15
> > > 15:48:09.88--ClientSession(5978600)--Connection(23637841)--Thread(Thread[main,5,main])--UPDATE
> > >
> > > product SET jdo_version = ? WHERE ((product_id = ?) AND (jdo_version =
> > > ?))
> > >     bind => [43, 30, 42]
> > > [EL Fine]: 2010-03-15
> > >
> > > What can I do to avoid this? Or is this a bug of EclipseLink?
> > >
> > > Kind Regards, Michael
> > > _______________________________________________
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>
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