Hi Édouard. This is a known issue -- at the moment, there is no good way to
model trees in the datastore where all nodes are of the same type. As others
have suggested, you can use more than one class with the same properties to
do this, which should work for shallow trees. You may also be able to
Thank you Maciej for your answer.
But I think that my problem is not related to any empty field. The
problem of storage arises as soon as you define twice a persistent
field which is a list of the same type, as I explained earlier. The
only work-around I found is to duplicate the listed
Hi, i think your problem is here:
@Persistent
private ListB list1 = new ArrayListB();
you use a List, but you assing an ArrayList. That because the datastore
makes different structures for different types of collection.
To fix that, your code should be:
@Persistent
private ArrayList B list1
