Question

Problem description:

I need to implement 2 classes like following:

class A1 {
 common_method1();
 common_method2();
 foo1();
};

class A2 {
 common_method1();
 common_method2();
 foo2();
};

foo1() and foo2() has different logic.
foo1() and foo2() may have different args and return values.
common methods are the same OR have similar logic.

Target:
To implement factory that is able to generate A1 or A2 objects.
After call to factory::create() use foo1() or foo2() method respectively to the type of the object generated.

Question
How better to implement such logic in C++ C++/CLI?

THANKS!

Answer 1

I think this is definitely a standard inheritance pattern. Create a base class Parent, which implements common_method1 and common_method2. Create classes A1 and A2 which inherit from Parent.

If you need to do some special casing in one of the common_method1 or common_method2 methods in either A1 or A2, make the methods virtual in Parent.

Implement foo1 and foo2 in respectively A1 and A2.

EDIT: If I understand you correctly, you want to create a factory that returns a Parent type reference (abstract class). If you want to always foo1 on A1 objects, and foo2 on A2 objects, simply create a virtual method bar in the Parent interface, which, overriden in A1, will simply call foo1, and, overriden in A2, will simply call foo2.