6. Final: Preventing Inheritance & Overriding

Scenario

What happens if we try to extend a final class or override a final method? (Theoretical since it won't compile, but important for concepts).

Code Block

final class SecurityConfig {
    final void validate() {
        System.out.println("Standard Validation");
    }
}

// class HackConfig extends SecurityConfig { } // COMPILE ERROR: Cannot inherit from final

class Base {
    final void secret() { System.out.println("Base Secret"); }
}

class Derived extends Base {
    // void secret() { } // COMPILE ERROR: Cannot override final method
}

public class Main {
    public static void main(String[] args) {
        new Base().secret();
    }
}

Take Your Shot

Predicted Output

Type exactly what you think will be printed in the console.