abstract-methods

Default implementations of Abstract methods

I am dealing with a large codebase that has a lot of classes and a lot of abstract methods on these classes. I am interested in peoples opinions about what I should do in the following situation. If I have a class Parent-A with an abstract method. There will only be 2 children. If Child-B implements AbstractMethodA but Child-B does ...

In Java, when should I use an abstract method in an interface?

I have the following interface in Java public interface IFoo { public abstract void foo(); public void bar(); } What is the difference between foo() and bar()? When should I use abstract? Both seem to accomplish what I want unless I'm missing something subtle? Update Duplicate of Why would one declare a Java interface method...

abstract method override in Derived class, how to make private

Hi I have a class "A" with as abstract method protected abstract List<Contributor> GetContributors(List<SyndicationPerson> contributersList); I want to override this method in derived class "B" with following conditions It should be private to B class. compiler does not allow me to declare this Method as private in derived class "...

C++/CLI : How do I declare abstract (in C#) class and method in C++/CLI?

What is the equivalent of the following C# code in C++/CLI? public abstract class SomeClass { public abstract String SomeMethod(); } ...

Should an abstract class have at least one abstract method?

Is it necessary for an abstract class to have at least one abstract method? ...

Should I Teach My Son Programming? What approaches should I take?

I was wondering if it's a good idea to teach object oriented programming to my son? I was never really good at math as a kid, but I think since I've started programming it's given me a greater ability to understand math by being better able to visualise relationships between abstract models. I thought it might give him a better advantage...

"Abstract static" method - how?

There are already several SO questions on why there is not abstract static method/field as such, but I'm wondering about how one would go about implementing the following psuedo-code: class Animal { abstract static int getNumberOfLegs(); // not possible } class Chicken inherits Animal { static int getNumberOfLegs() { return 2; ...

When and Why to use abstract classes/methods?

I have some basic questions about abstract classes/methods.I know basic use of abstract classes is to create templates for future classes. But are there any more uses of them ? When should you prefer them over interfaces and when not ? Also when are abstract methods useful ? ...

Polymorphism and casting problem

In order to explain my problem here is an example namespace CheckAbstarct { class Program { static void Main(string[] args) { myAbstarctClass mac1 = ObjectFactory.ObjectCreator("aaa"); myAbstarctClass mac2 = ObjectFactory.ObjectCreator("bbb"); mac1.changeMyString(); mac2.changeMyString(); ...

Default implementation or abstract method?

Is it better to put a default implementation of a method in a superclass, and override it when subclasses want to deviate from this, or should you just leave the superclass method abstract, and have the normal implementation repeated across many subclasses? For example, a project I am involved in has a class that is used to specify the ...

C# design: Why is new/override required on abstract methods but not on virtual methods?

Hi all Why is new/override required on abstract methods but not on virtual methods? Sample 1: abstract class ShapesClass { abstract public int Area(); // abstract! } class Square : ShapesClass { int x, y; public int Area() // Error: missing 'override' or 'new' { return x * y; } } The compiler will show ...

How to require implementation of method in Python?

I'm using duck typing in Python. def flagItem(object_to_flag, account_flagging, flag_type, is_flagged): if flag_type == Flags.OFFENSIVE: object_to_flag.is_offensive=is_flagged elif flag_type == Flags.SPAM: object_to_flag.is_spam=is_flagged object_to_flag.is_active=(not is_flagged) object_to_flag.cleanup(...

Ways to keep abstract method server side for WCF

We are enforcing all our domain objects to implement GetHashCode. namespace Core { [Serializable] public abstract class DomainObject { public abstract override int GetHashCode(); } } namespace Entity.Domain { [Serializable] [DataContract] public partial class IdCard : DomainObject { private System.Int32 _effDte;...