Uniquing (a guarantee that only one copy of object with a given ID exists
within the same ObjectContext) is Cayenne feature that works consistently
across all releases since the early days. Please DON'T attempt to override
equals and hashCode. The problem is likely elsewhere (likely your 2 objects
coming from different contexts). And your implementation is not correct from
the Cayenne POV (it doesn't take context into account) and will likely cause
other problems.
Cheers,
Andrus
On Oct 13, 2011, at 1:53 PM, Bruno René Santos wrote:
> Hello all,
>
> I've come accross a problem with the CayenneDataObjects. For some reason
> Cayenne created two different instances of the same database object. This
> made that the function equals and hashCode returned different values for the
> same data object (conceptually). I checked the CayenneDataObject and the
> hashCode function is not overriden anywhere, leading to this problem. As I
> already have extended the CayenneDataObject I only had to override the
> following functions:
>
> @Override
> public boolean equals(Object obj) {
> if (obj instanceof HolosDataObject)
> return getObjectId().equals(((HolosDataObject) obj).getObjectId());
> return false;
> }
>
> @Override
> public int hashCode() {
> return getObjectId().hashCode();
> }
>
> Which fixed the problem. I am using cayenne 3.0.1. Shouldn't these
> functions, or some sort of version of them, be present in
> CayenneDataObject/PersistentDataObject?
>
> Regards
> Bruno Santos
>
> --
> Bruno René Santos | [email protected] | Gestor de Projectos | Analista |
> Programador | Investigador
>
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> Rua dos Inventores . Quinta da Torre . 2825 - 182 Caparica . Portugal
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>
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