Iterating through strategy design pattern

Question

I have a list of algorithms that I want to run on a dataset. For example, say my dataset is a list of addresses. I need to check the validity of the addresses but I have several different algorithms for validating. Say I have validation_one and validation_two . But in the future I will need to add validation_three , validation_four , etc. I need ALL of the validations to run on the address list, even the new ones when they get added.

Is there a design pattern that fits into this? I know strategy is for selecting an algorithm but I specifically need a way to apply all the algorithms on the dataset.

Answer 1

You have not stated a language.. but assuming it has generics.

Given a DataSet<T>

Assuming also that there is no cross validation required (ie each T can be validated entirely by its own data)

Declare a validation Strategy, with a single method.

IValidate<T>{bool validate(T item);} 

validation_one, validation_two…. Will implement this strategy

Have a List<IValidate<T>> which you can add and remove implementations to.

Foreach item in the dataset call each strategy in the list.

It's then your choice to how you deal with failures.

Answer 2

这听起来像责任链，链中的所有处理程序都接受请求并将其传递给下一个处理程序。

Answer 3

Composite.

Which is basically what the two other answers equate to.

The first answer is an implementation of COmposite. The second one is usign Chain of Rersponsibility as a Composite.