Since Java 8, interfaces can also have non-public and static methods.
I understand that interfaces can't have non-final non-static instance variables, which just seems like a limitation abstract classes don't suffer from.
The only real difference that could change which to use would be, that multiple interfaces can be implemented in the same class, while abstract classes can only be extended once per class; so, if this is the only difference, why create interfaces, instead of making multiple inheritance possible?
