I am reading Righting Software by Juval Lowy. It talks about volatility based decomposition and why we should prefer it over functional or domain decomposition. Then it talks about Manager and Engine in The Method.
a particular use case can change in only two ways: Either the sequence itself changes or the activities within the use case change.
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Manager components encapsulate the volatility in the sequence, whereas Engine components encapsulate the volatility in the activity.
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Since use cases are often related, Managers tend to encapsulate a family of logically related use cases, such as those in a particular subsystem.
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Managers may use zero or more Engines. Engines may be shared between Managers.
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Managers can directly call Engines.
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Engines are really just an expression of the Strategy design pattern used to implement the activities within the Managers’ workflows.
In the book I did not find any code example so not understanding how to implement it or how the Manager or Engine actually look like in The Method.
I understand that I have to somehow use the strategy pattern. But, I am not understanding how to do it?
Please help.
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