What is the difference between final Class and Class?

Question

What is the difference between final Class and Class?

final class A {

}

class B {    

}

Answer 1

Other answers are already given enough understanding about final keyword. I want to explain by some example.

Consider below example without final Keyword.

class A {
   public var name: String
   var breed: String

    init(name: String, breed: String) {
        self.name = name
        self.breed = breed
    }
}
class B:A{
    override init(name: String, breed: String) {
        super.init(name: name, breed: breed)
    }
}

In above code it allow to overwrite the varible of it's super class. While Class with final keyword don't allow it. Refer below example.

final class A {
   public var name: String
   var breed: String

    init(name: String, breed: String) {
        self.name = name
        self.breed = breed
    }
}

class B:A{
    **//ERROR:inheritance from a final class 'A' class B**
    override init(name: String, breed: String) {
        super.init(name: name, breed: breed)
    }
}

Above code will give error inheritance from a final class A class B