protected E2 getChildOf(E1 parent) { Collection<? extends RefObject> c = super.query(true, parent); assert (c.size() <= 1); if (c.isEmpty()) { return null; } else { return end2GenericClass.cast(c.iterator().next()); } }
protected E1 getParentOf(E2 child) { Collection<? extends RefObject> c = super.query(false, child); assert (c.size() <= 1); if (c.isEmpty()) { return null; } else { return end1GenericClass.cast(c.iterator().next()); } }