Why is it not allowed to narrow down scope of a method while overriding

Question

In Java, when I override a method the compiler flags off any attempt to narrow down the visibility as an error. For ex: I can\'t override a public method as protected, while

Answer 1

A subclass should always satisfy the contract of the superclass. See Liskov Substitution principle.

The visibility of methods is part of this contract. So anything publicly visible in the superclass should be public in the subclass as well.