You have an interface that allows you to treat all worker classes – classes that handle a specific type of work – as just one type: IWorker;
You want your worker classes to be able to do their work without having to check their backs every step of the way.
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CanHandle – Handle pattern conundrum
When you have multiple classes implementing an IWorker interface with a CanHandle and Handle method, such as
you find yourself in a conundrum: should you call CanHandle again from Handle?
If you don’t, someone could pass in work that a worker isn’t designed to handle and that can lead to a multitude of different exceptions or subtle,
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You have multiple Worker classes that can each handle a one or more types of command. Your IWorker interface offers two methods: CanHandle and Handle.
Perfect.
Anyone with work to be done can now find a worker that says “yay, I can handle this” and then pass off the work to that worker.
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