What is the difference between the template method and the strategy patterns?

Question

Can someone please explain to me what is the difference between the template method pattern and the strategy pattern is?

As far as I can tell they are 99% the same -

Answer 1

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Similarities

Strategy and Template method patterns have a lot of similarities between them. Both Strategy and Template method patterns can be used for satisfying the Open-Closed Principle and making the software module easy to extend without changing its code. Both patterns represent separation of generic functionality from the detailed implementation of that functionality. However, they differ a little in terms of granularity they offer.

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Differences

Here are some of the differences I have observed while studying these two patterns:

1. In Strategy, the coupling between the client and strategy is more loose whereas in Template Method, the two modules are more tightly coupled.
2. In Strategy, mostly an interface is used though abstract class can also be used depending on the situation, and concrete class is not used whereas in Template method mostly abstract class or concrete class is used, interface is not used.
3. In Strategy pattern, generally entire behaviour of the class is represented in terms of an interface, on the other hand, Template method is used for reducing code duplication and the boilerplate code is defined in base framework or abstract class. In Template Method, there can even be a concrete class with default implementation.
4. In simple words, you can change the entire strategy (algorithm) in Strategy pattern, however, in Template method, only some things change (parts of algorithm) and rest of the things remain unchanged. In Template Method, the invariant steps are implemented in an abstract base class, while the variant steps are either given a default implementation, or no implementation at all. In Template method, the component designer mandates the required steps of an algorithm, and the ordering of the steps, but allows the component client to extend or replace some number of these steps.

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Image is taken from the bitesized blog.