Ruby使用设计模式中的代理模式与装饰模式的代码实例

这样写的话，功能是实现了，问题是如果增加“超人”的装扮，就要修改Person类，违反了开放-封闭原则。

 

代码版本二

# -*- encoding: utf-8 -*-

class Person
 attr_accessor :name
 
 def initialize(name)
  @name = name
 enddef show
  puts "*****装扮的#{name}nn"
 end

end


class Finery
 def show
 end
end

class TShirts < Finery
 def show
  puts '大T恤'
 end
end

class BigTrouser < Finery
 def show
  puts '垮裤'
 end
end

class Sneakers < Finery
 def show
  puts '破球鞋'
 end
end

class Suit < Finery
 def show
  puts '西装'
 end
end

class Tie < Finery
 def show
  puts '领带'
 end
end


class LeatherShoes < Finery
 def show
  puts '皮鞋'
 end
end


xc=Person.new('小菜')
ts = TShirts.new
bt = BigTrouser.new
sk = Sneakers.new
puts "******第一种装扮"
ts.show
bt.show
sk.show
xc.show


suit = Suit.new
tie = Tie.new
ls = LeatherShoes.new
puts "******第二种装扮"
suit.show
tie.show
ls.show
xc.show

这样改了之后，如果增加超人装扮，确实不需要去修改Person类。存在的问题是，各种衣服是独立的，并且暴露在外边的，就是一件一件穿的，没有顺序，没有控制。

代码版本三

# -*- encoding: utf-8 -*-

class Person
 attr_accessor :name
 
 def initialize(name=nil)
  @name = name
 end
 
 def show
  puts "*****装扮的#{name}nn"
 end

end


class Finery < Person
 attr_accessor :componet

 def decorate(componet)
  @componet = componet
 end

 def show
  componet.show if componet
 end
end

class TShirts < Finery
 def show
  super
  puts '大T恤'
 end
end

class BigTrouser < Finery
 def show
  super
  puts '垮裤'
 end
end

class Sneakers < Finery
 def show
  super
  puts '破球鞋'
 end
end

class Suit < Finery
 def show
  super
  puts '西装'
 end
end

class Tie < Finery
 def show
  super
  puts '领带'
 end
end


class LeatherShoes < Finery
 def show
  super
  puts '皮鞋'
 end
end


xc=Person.new('小菜')
ts = TShirts.new
bt = BigTrouser.new
sk = Sneakers.new
puts "******第一种装扮"
ts.decorate xc
bt.decorate ts
sk.decorate bt
sk.show


suit = Suit.new
tie = Tie.new
ls = LeatherShoes.new
puts "******第二种装扮"
suit.decorate xc
tie.decorate suit
ls.decorate bt
ls.show