Python使用设计模式中的责任链模式与迭代器模式的示例
(编辑:jimmy 日期: 2024/11/19 浏览:3 次 )
责任链模式
责任链模式:将能处理请求的对象连成一条链,并沿着这条链传递该请求,直到有一个对象处理请求为止,避免请求的发送者和接收者之间的耦合关系。
#encoding=utf-8 # #by panda #职责连模式 def printInfo(info): print unicode(info, 'utf-8').encode('gbk') #抽象职责类 class Manager(): successor = None name = '' def __init__(self, name): self.name = name def SetSuccessor(self, successor): self.successor = successor def HandleRequest(self, request): pass #具体职责类:经理 class CommonManager(Manager): def HandleRequest(self, request): if request.RequestType == '请假' and request.Number <= 2: printInfo('%s:%s 数量%d 被批准' % (self.name, request.RequestContent, request.Number)) else: if self.successor != None: self.successor.HandleRequest(request) #具体职责类:总监 class Majordomo(Manager): def HandleRequest(self, request): if request.RequestType == '请假' and request.Number <= 5: printInfo('%s:%s 数量%d 被批准' % (self.name, request.RequestContent, request.Number)) else: if self.successor != None: self.successor.HandleRequest(request) #具体职责类:总经理 class GeneralManager(Manager): def HandleRequest(self, request): if request.RequestType == '请假': printInfo('%s:%s 数量%d 被批准' % (self.name, request.RequestContent, request.Number)) elif request.RequestType == '加薪' and request.Number <= 500: printInfo('%s:%s 数量%d 被批准' % (self.name, request.RequestContent, request.Number)) elif request.RequestType == '加薪' and request.Number > 500: printInfo('%s:%s 数量%d 再说吧' % (self.name, request.RequestContent, request.Number)) class Request(): RequestType = '' RequestContent = '' Number = 0 def clientUI(): jinLi = CommonManager('金力') zongJian = Majordomo('宗健') zhongJingLi = GeneralManager('钟金利') jinLi.SetSuccessor(zongJian) zongJian.SetSuccessor(zhongJingLi) request = Request() request.RequestType = '请假' request.RequestContent = '小菜请假' request.Number = 1 jinLi.HandleRequest(request) request.RequestType = '请假' request.RequestContent = '小菜请假' request.Number = 5 jinLi.HandleRequest(request) request.RequestType = '加薪' request.RequestContent = '小菜要求加薪' request.Number = 500 jinLi.HandleRequest(request) request.RequestType = '加薪' request.RequestContent = '小菜要求加薪' request.Number = 1000 jinLi.HandleRequest(request) return if __name__ == '__main__': clientUI();
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迭代器模式
迭代器模式:提供一种方法顺序访问一个聚合对象中的各个元素,而又不暴露该对象的内部表示。
python内置支持这种模式,所以一般来说,不用自己写,
#encoding=utf-8 # #by panda #迭代器(Iterator)模式 def printInfo(info): print unicode(info, 'utf-8').encode('gbk') #迭代器抽象类 class Iterator: def First(self): pass def Next(self): pass def IsDone(self): pass def CurrentItem(self): pass #集合抽象类 class Aggregate: def CreateIterator(self): pass #具体迭代器类: class ConcreteIterator(Iterator): aggregate = None current = 0 def __init__(self, aggregate): self.aggregate = aggregate self.current = 0 def First(self): return self.aggregate[0] def Next(self): ret = None self.current += 1 if(self.current < len(self.aggregate)): ret = self.aggregate[self.current] return ret def IsDone(self): if(self.current < len(self.aggregate)): return False else: return True def CurrentItem(self): ret = None if(self.current < len(self.aggregate)): ret = self.aggregate[self.current] return ret #具体集合类 class ConcreteAggregate(Aggregate): items = None def __init__(self): self.items = [] def clientUI(): a = ConcreteAggregate() a.items.append('大鸟') a.items.append('小菜') a.items.append('行李') a.items.append('老外') a.items.append('公交内部员工') a.items.append('小偷') printInfo('---------迭代器模式-------------') i = ConcreteIterator(a.items) item = i.First() while(False == i.IsDone()): printInfo("%s 请买车票!" % i.CurrentItem()); i.Next() printInfo('\n---------python内部迭代-------------') for item in a.items: printInfo("%s 请买车票!" % item); return if __name__ == '__main__': clientUI();
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