Can an object subclass other object?

Answer 1

A class can extend or be the subclass of another class. Objects are instances of classes. So you can have objects of the (super)class and objects of the subclass.

Answer 2

im currently learning c++ instead of java.. but i think the fundamental is the same.. Yes, an object can be within an another object.. such as an object in an object.. ^_^

Answer 3

YES