db4o does not directly support the following two refactorings:
Note that interfaces don't influence the inheritance-hierarchy and can be added and removed at any time.
For example we've following classes:
In this example you cannot introduce a 'Animal' class above the 'Mammal' or add another class between 'Mammal' and 'Primate'. Also you shouldn't remove an class form the inheritance-hierarchy.
Currently the only possible solution for this refactoring is this.
Take a look at the example to how to add a class into the hierarchy. See "Inserting Class Into A Hierarchy".
Or how you can remove a class from the inheritance hierarchy. See "Removing Class From A Hierarchy"