Final Classes
final class basically used when we are working n the class declaration that time we are using the final keyword when we would like to show the \" the class can\'t be subclasses\" .
We also can say in different terms: no other class can ever extend (inherit from) a final class, and any attempts to do so will give us a compiler error.
We should make a final class only we we need an absolute guarantee that none of the methods in that class will ever be overridden.