Thanks Mark and Fou-Lou;
I kind of get this abstract stuff I'm learning in Computer Science; in addition, sometimes I had to make sure I was using the right declaration types because I use a file with the main method and a file with a bunch of class methods to refer to.
class ConcreteOuter extends outer
I was thinking of taking this out of my snippet of code, as I do have an extension of a class in the main method or subclass file. Although it may change the function, I would have to try to actually include an implementation, since that this is not
abstract class ConcreteOuter extends outer