On Dec 11, 2007, at 3:05 PM, Kevin Menard (JIRA) wrote:
However, when using the default key, calling
ObjRelationship#getMapKey() returns null. Is that expected behavior
as well? If so, I think I'd like to see that changed. I'm fine
with defaults not being specified in the DataMap, but the runtime
model should have all the info.
Yes this is expected behavior. What NULL means is simply that there is
no ObjAttribute for the key. Since id's in Cayenne are not class
properties by default, there's nothing to map to. Here is the logic to
extract the key in runtime:
IdMapKeyAccessor.java:
ObjectId id = ((Persistent) object).getObjectId();
if (id.isTemporary()) {
return id;
}
Map map = id.getIdSnapshot();
if (map.size() == 1) {
Map.Entry pkEntry = (Map.Entry)
map.entrySet().iterator().next();
return pkEntry.getValue();
}
return id;
So you see, there is a bit of fuzziness - a key can be an ObjectId for
multi-column PK and for NEW objects, or it can be a single PK value
for committed single-column PK.
Andrus
