Mailing-List: contact cayenne-user-help@incubator.apache.org; run by ezmlm
Precedence: bulk
Reply-To: cayenne-user@incubator.apache.org
Received-SPF: neutral (asf.osuosl.org: 218.214.79.9 is neither permitted nor
 denied by domain of marcin@ish.com.au)
Mime-Version: 1.0 (Apple Message framework v752.2)
In-Reply-To: <44F20182.2030806@rcda.ca>
References: <44F20182.2030806@rcda.ca>
Content-Type: text/plain; charset=ISO-8859-1; delsp=yes; format=flowed
Message-Id: <78B591AA-8116-482C-9BA0-009FE03AADBC@ish.com.au>
Content-Transfer-Encoding: quoted-printable
From: Marcin Skladaniec <marcin@ish.com.au>
Subject: Re: DataContext synchronization bug ?
Date: Mon, 28 Aug 2006 08:26:19 +1000
To: cayenne-user@incubator.apache.org

Hello Jonathan

Please take a closer look on the localObject() method.
Straight from javadocs :
"Returns an object local to this DataContext and matching the =20
ObjectId. If prototype is not null, local object is refreshed with =20
the prototype values.

In case you pass a non-null second parameter, you are responsible for =20=

setting correct persistence state of the returned local object, as =20
generally there is no way for Cayenne to determine the resulting =20
local object state."

If you have still problems please mention what version of cayenne are =20=

you using.

Marcin
-------------------------->
ish
http://www.ish.com.au
Level 1, 30 Wilson Street Newtown 2042 Australia
phone +61 2 9550 5001   fax +61 2 9550 4001


On 28/08/2006, at 6:33 AM, Jonathan B=E9lisle wrote:

> Hi, maybe someone can help me here.
>
> I'm trying to copy a dataObject to another dataContext while keeping
> it's modified state so that it will be correctly committed to the =20
> db by the second dataContext.
>
> Let say we have an entity with an attribute Name and a relationship =20=

> Category.
> The object 1000001 exist in the db and has a Name and a Category
>
> //Create the dataContext
> DataContext dc1=3D DataContext.createDataContext();
> DataContext dc2=3D DataContext.createDataContext();
>
> //Get object from db. Modify the name.
> Animal from=3D (Animal) DataObjectUtils.objectForPK(dc1, new ObjectId=20=

> ("Animal", "animalId", 1000001));
> from.setName("XXX" + new SecureRandom().nextInt());
>
> //Get local object to dc2
> //I cannot use dc2.localObject(from.getObjectId(), from);
> //because the dc2 won't see the modification made in dc1.
> Animal to=3D (Animal) dc2.localObject(from.getObjectId(), null);
> dc2.getObjectStore().resolveHollow(to);
>
> //Copy the attributes from object1 to object2      String attName;
> ObjAttribute objAttribute;
> ObjEntity objEntity=3D from.getObjectContext().getEntityResolver=20
> ().lookupObjEntity(to);
> Iterator attributes =3D objEntity.getAttributes().iterator();
> while (attributes.hasNext()) {
>    objAttribute =3D (ObjAttribute) attributes.next();
>    attName=3D objAttribute.getName();
>
>    to.writeProperty(attName, from.readPropertyDirectly(attName));
> }
>       dc2.commitChanges();
>
> System.out.println(from);
> System.out.println(to);
>
> Everything is committed correctly to the db but the object from has =20=

> now a Category =3D null
>
> The problem is after the dc2.commitChanges() and
> it comes from =20
> org.objectstyle.cayenne.event.EventManager.DispatchThread.run() =20
> witch is firing an event to set the relationship Category to null.
> I don't know why it is doing that.
> I am doing something wrong ? Is it a bug in cayenne ?
> And i need context synchronization so turning it off is not an option.
>
> I really need help on this one, can someone help me ?
>
> Jonathan