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43 lines
664 B
Ruby
43 lines
664 B
Ruby
# Define a family of algorithms, encapsulate each one, and make them
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# interchangeable. Strategy lets the algorithm vary independently from clients that use it.
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# Strategies
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class StrategyOne
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def use
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puts "Strategy one"
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end
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end
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class StrategyTwo
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def use
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puts "Strategy two"
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end
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end
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class StrategyThree
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def use
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puts "Strategy three"
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end
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end
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# Client
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class Context
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@@default_strategy = StrategyOne.new
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def set_strategy(strategy)
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@strategy = strategy
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end
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def use
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@strategy.use
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end
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end
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# Usage
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context = Context.new
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context.use # => "Strategy one"
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context.set_strategy StrategyTwo.new
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context.use # => "Strategy two"
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