20 lines
1.0 KiB
Markdown
20 lines
1.0 KiB
Markdown
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---
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layout: pattern
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title: Strategy
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folder: strategy
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categories: pattern_cat
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tags: pattern_tag
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---
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**Intent:** Define a family of algorithms, encapsulate each one, and make them
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interchangeable. Strategy lets the algorithm vary independently from clients
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that use it.
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**Applicability:** Use the Strategy pattern when
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* many related classes differ only in their behavior. Strategies provide a way to configure a class either one of many behaviors
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* you need different variants of an algorithm. for example, you might define algorithms reflecting different space/time trade-offs. Strategies can be used when these variants are implemented as a class hierarchy of algorithms
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* an algorithm uses data that clients shouldn't know about. Use the Strategy pattern to avoid exposing complex, algorithm-specific data structures
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* a class defines many behaviors, and these appear as multiple conditional statements in its operations. Instead of many conditionals, move related conditional branches into their own Strategy class
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