66 lines
1.4 KiB
Ruby
66 lines
1.4 KiB
Ruby
# The very simple idea behind the Builder pattern is that you encapsulate object
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# construction logic behind a class of its own. The builder class takes charge of
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# assembling all the components of a complex object. Each builder has an interface
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# that lets you specify the configuration of your new object step by step. In a
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# sense, a builder is a sort of like a multipart new method, where objects are
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# created in an extended process instead of all in one shot.
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# Classes witch are used in builder
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class Computer
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# Implementation
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end
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class TurboCPU
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# Implementation
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end
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class Drive
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# Implementation
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end
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# Builder
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class ComputerBuilder
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attr_reader :computer
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def initialize
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@computer = Computer.new
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end
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def turbo(has_turbo_cpu = true)
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computer.cpu = TurboCPU.new
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end
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def display=(display)
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computer.display=display
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end
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def memory_size=(size_in_mb)
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computer.memory_size = size_in_mb
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end
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def add_cd(writer=false)
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computer.drives << Drive.new(:cd, 760, writer)
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end
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def add_dvd(writer=false)
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computer.drives << Drive.new(:dvd, 4000, writer)
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end
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def add_hard_disk(size_in_mb)
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computer.drives << Drive.new(:hard_disk, size_in_mb, true)
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end
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end
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# Usage
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computer_builder = ComputerBuilder.new
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computer_builder.turbo false
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computer_builder.display = 'Monitor'
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computer_builder.add_dvd false
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computer_builder.add_cd = false
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computer_builder.memory_size = '12mb'
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computer = computer_builder.computer
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