I am trying to check if a parameter is of a certain type when instantiating a subclass of a superclass, and I keep getting an error that appears to be associated with my method of checking of the argument type. The debugger won't even let me include a breakpoint without throwing the error "A constructor call to superclass appears after the object is used, or after a return." I think it's pretty obvious what line of code breaks my classes, but why am I not allowed to do this type checking? What other ways are there to confirm that my arguments are of a particular type? Code below.