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