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命令模式(python)

 

命令模式:将一个请求封装为一个对象,从而使你可用不同的请求对客户进行参数化;支持对请求排队、记录请求日志,以及可撤销的操作。

优点:把请求一个操作的对象与知道怎么执行一个操作的对象分隔开。

#encoding=utf-8 

#by panda 

#命令模式 

 

def printInfo(info): 

    print unicode(info, 'utf-8').encode('gbk') 

 

import time 

#Command 

class Command(): 

    receiver = None 

    def __init__(self, receiver): 

        self.receiver = receiver 

     

    def Execute(self): 

        pass     

 

#具体命令类:拷羊肉串 

class BakeMuttonCommand(Command): 

    def SetHandsetSoft(self, receiver): 

        Command.__init__(self,receiver) 

     

    def Execute(self): 

        self.receiver.BakeMutton()    

         

    def ToString(self): 

        return '拷羊肉串' 

     

         

#具体命令类:拷鸡翅 

class BakeChickenWingCommand(Command): 

    def SetHandsetSoft(self, receiver): 

        Command.__init__(self,receiver) 

     

    def Execute(self): 

        self.receiver.BakeChickenWing()    

     

    def ToString(self): 

        return '拷鸡翅' 

         

#Receiver:拷肉串的人 

class Barbecuer():  

    def BakeChickenWing(self): 

        printInfo('拷鸡翅!') 

     

    def BakeMutton(self): 

        printInfo('拷羊肉串!') 

         

#Invoker:服务员 

class Waiter(): 

    commandList = [] 

     

    def SetOrder(self,command): 

        printInfo('%s 增加订单:%s' % (time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(time.time())),command.ToString())) 

        self.commandList.append(command) 

     

    def CancelOrder(self,command): 

        printInfo('%s 取消订单:%s' % (time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(time.time())),command.ToString())) 

        self.commandList.remove(command) 

     

    def Notify(self): 

        printInfo('\n通知:') 

        for command in self.commandList: 

            command.Execute() 

 

    def Run(self): 

        printInfo('运行手机通信录') 

 

def clientUI(): 

    boy = Barbecuer() 

    bakeMuttonCommand1 = BakeMuttonCommand(boy) 

    bakeMuttonCommand2 = BakeMuttonCommand(boy) 

    bakeChickenWingCommand1 = BakeChickenWingCommand(boy) 

    girl = Waiter() 

     

    girl.SetOrder(bakeMuttonCommand1) 

    girl.SetOrder(bakeMuttonCommand2) 

    girl.SetOrder(bakeChickenWingCommand1) 

    girl.CancelOrder(bakeMuttonCommand1) 

    girl.Notify() 

    return 

 

if __name__ == '__main__': 

    clientUI(); 

 

 

类图:

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补充:Web开发 , Python ,
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