1
vote
3answers
160 views

Extending a struct. Using helper classes rather than composition

I have a struct which I want to add static methods to. Yes, you guessed right I'm talking about Datetime. It's a pretty typical requirement to add MyCustomParse. It happens to return Datetime?, so ...
4
votes
2answers
867 views

How to replace inheritance with composition in this case?

I've recently read several articles about the advantages of the composition over inheritance. Their authors said that you can always replace inheritance with composition (to be precise, they say they ...
2
votes
1answer
86 views

Testing complex compositions

I have a rather large collection of classes which check and mutate a given data structure. They can be composed via the composition pattern into arbitrarily complex tree-like structures. The final ...
0
votes
0answers
73 views

does class reference itself static anti pattern in prism

I have an application and my desing approach look like this: class Manager { public int State; static Manager _instance = null; public static Manager Instance { get { return ...
1
vote
2answers
130 views

Visitor only applicable when using the Composite pattern?

For a long time I've tried to get my head wrapped around the visitor pattern, and somehow this thing keeps being rather fuzzy to me. I'm currently under the impression it is only useful to apply ...
1
vote
2answers
93 views

Inheritance vs 'specification' by fields

I'm currently reading 'Head first design patterns', and already the first chapter threw some questions towards me. This chapter introduces the 'prefer composition over inheritance' design principle, ...
1
vote
2answers
133 views

Alternatives to inheritance on complex structures?

I'm working on an ASP.NET Webforms project, using the MVP Pattern (which the presenters as you may know use a Page Controller pattern). I'm given a rather complex inheritance chain for my controllers. ...
3
votes
2answers
177 views

How to use the Decorator pattern to add little functionality to big objects?

This question regards the usage of the Decorator pattern to add little functionality to objects of large classes. Following the classic Decorator pattern, please consider the following class ...
3
votes
3answers
207 views

Why should one subclass instead of composite when using the Factory Method design pattern?

I'm currently learning about design patterns. I learned about the Factory Method pattern. This pattern means that in order to implement a factory to create objects, one should subclass the class that ...
1
vote
3answers
149 views

Does this in the Observer pattern count as composition?

In a classic implementation of the Observer design pattern, the subject has a list of references to all of it's observers, and each observer might have a reference to it's subject. Is this considered ...
0
votes
2answers
249 views

Inheritance versus Composition in a business application

I have a training management and tracking system, with a high level structure as follows: We have a Role1, e.g. Manager, Shift-boss, miner, etc. and a Candidate, training for that Role. The role has ...