Hello !

I think you have it all right, but just in case:
dataObjectInContext2= context2.localObject (dataObjectInContext1.getObjectId(), dataObjectInContext1); dataObjectInContext2.setPersistenceState (dataObjectInContext1.getPersistenceState() ); //In case that the object 1 state is NEW
context2.commitChanges();
Is it that dead simple or you are doing some more things ?
I don't see a reason why it is not working for you.
Marcin


On 29/08/2006, at 4:49 AM, Jonathan Bélisle wrote:

Hi Marcin,

I've already looked at localObject() and it's not good.
Here's why ?

You have a data object : dataObjectInContext1
You modify a property : dataObjectInContext1.setName("the new name");
You copy it to the second dataContext and modify it's persistenceState

dataObjectInContext2= context2.localObject (dataObjectInContext1.getObjectId(), dataObjectInContext1); dataObjectInContext2.setPersistenceState (PersistenceState.MODIFIED);

Everything is ok till now but here is the problem :

   dataObjectInContext2.commitChanges();

Nothing will be written to the database because context2 did not track changes of dataObjectInContext2.
That's why i'm not using localObject().
Is there a way that dataObjectInContext2 will be committed using localObject() ?

I'm using Cayenne 1.2

Jonathan.


Marcin Skladaniec wrote:
Hello Jonathan

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

In case you pass a non-null second parameter, you are responsible for setting correct persistence state of the returned local object, as generally there is no way for Cayenne to determine the resulting local object state."

If you have still problems please mention what version of cayenne are 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 Bélisle 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 db by the second dataContext.

Let say we have an entity with an attribute Name and a relationship Category.
The object 1000001 exist in the db and has a Name and a Category

//Create the dataContext
DataContext dc1= DataContext.createDataContext();
DataContext dc2= DataContext.createDataContext();

//Get object from db. Modify the name.
Animal from= (Animal) DataObjectUtils.objectForPK(dc1, new ObjectId("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= (Animal) dc2.localObject(from.getObjectId(), null);
dc2.getObjectStore().resolveHollow(to);

//Copy the attributes from object1 to object2      String attName;
ObjAttribute objAttribute;
ObjEntity objEntity= from.getObjectContext().getEntityResolver ().lookupObjEntity(to);
Iterator attributes = objEntity.getAttributes().iterator();
while (attributes.hasNext()) {
   objAttribute = (ObjAttribute) attributes.next();
   attName= 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 now a Category = null

The problem is after the dc2.commitChanges() and
it comes from org.objectstyle.cayenne.event.EventManager.DispatchThread.run() 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









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


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