Higher Class Hierarchy vs Wider Class Spectrum

Question

I have a "Good Practice" Question:

Lets assume a case where one have many List Types

1. IObservableList With Events

2. IReadOnlyList Read Only

3. ISomeList Some List that perform additional operations

Is it better to define 6 classes Like

1. ObservableList:IList

2. ObservableReadonlyList:IList

3. ObservableSomeList:IList

4. ReadonlyList:IList

5. ReadonlySomeList:IList

6. ObservableReadonlySomeList:IList

or

Adapting one too another using 3 Classes:

1. ReadOnlyListAdapter : IList

2. ObservableListAdapter : IList

3. SomeListAdapter : IList

and instanciating with

IList MyObservableReadonlySomeList = new ReadonlyListAdapter(new ObservableListAdapter(new SomeListAdapter)));

Note:

i tend to like the 6 classes better, but what goes when there are 6 or 7 properties for a class??? 30-50 classes?

Thank you, have a nice day...

Answer 1

i tend to like the 6 classes better, but what goes when there are 6 or 7 properties for a class??? 30-50 classes?

You might want to look at the Decorator pattern. It may indeed be what you're actually doing with what you're calling adapters.