中介者模式

模式说明

所谓中介者模式就是用一个中介对象来封装一系列的对象交互，中介者使各对象不需要显式地相互引用，从而使其耦合松散，而且可以独立地改变它们之间的交互。

模式结构图

程序示例

说明：房主、租客与中介

代码：

class Mediator(object):

    def sendmsg(self,msg,person):

        pass



class Person(object):

    def __init__(self,name,mediator):

        self._name = name

        self._mediator = mediator

    def contact(self,msg):

        self._mediator.sendmsg(msg,self)

    def getmsg(self,msg):

        print ' %s get msg : %s' % (self._name,msg)



class HouseOwner(Person):

    pass

class Tenant(Person):

    pass



class ConcreteMediator(Mediator):

    def sethouseowner(self,houseowner):

        self._houseowner = houseowner

    def settenant(self,tenant):

        self._tenant = tenant



    def sendmsg(self,msg,person):

        if person != self._houseowner:

            self._houseowner.getmsg(msg)

        else:

            self._tenant.getmsg(msg)



if __name__ == '__main__':

    mediator = ConcreteMediator()

    #house owner find the mediator

    houseowner = HouseOwner('wang',mediator)

    #tenant find the mediator

    tenant = Tenant('li',mediator)



    #the mediator make the bridge between houser owner and tenant

    mediator.sethouseowner(houseowner)

    mediator.settenant(tenant)



    #houser owner and tenant can contact

    tenant.contact('any else houses?')

    houseowner.contact('yes!')

    print 'over!'



    houseowner1 = HouseOwner('chen',mediator)

    mediator.sethouseowner(houseowner1)



    tenant.contact('any else houses?')

    houseowner1.contact('yes!')



    houseowner.contact('yes!') # not the current houseowner,take as tenant

    

运行结果：

参考来源：

http://www.cnblogs.com/chenssy/p/3679190.html

http://www.cnblogs.com/wuyuegb2312/archive/2013/04/09/3008320.html