设计模式十九（中介者模式，python语言实现）

基本原理请参考相关资料，这里直接给实例。



基本说明：中介者模式，（ 仲裁者、集中控制），隔离了各个对象间的直接耦合



指挥中心分：灾害处理中心（DisasterDealCenter），边境处理中心（FrontierDealCenter）



处理小分队分：警犬巡逻队（SentryA），边境情报对（SentryB），边境缉毒队（sentryC）



小队间是平行级别，需要帮助时，向注册的指挥中心发出请求。

指挥中心根据请求，回复该小队，并安排其它小队配合

# -*- coding: GB18030 -*-
#######################################################
# 
# mediator.py
# Python implementation of the Class DisasterDealCenter
# Generated by Enterprise Architect
# Created on:      15-十二月-2012 13:26:57
# 
#######################################################

from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
from future_builtins import *
    

class Headquarters(object):
    """This class defines an interface for communicating with Colleague objects.
    """
    def __init__(self,name='司令部'):
        self.name=name
        pass

    def Request(self, sentry):
        pass

class DisasterDealCenter(Headquarters):
    """This class defines an interface for communicating with Colleague objects.
    """
    def __init__(self,name='灾害处理中心'):
        super(DisasterDealCenter,self).__init__(name)
        pass

    def Request(self, sentry):
        pass

class FrontierDealCenter(Headquarters):
    """This class defines an interface for communicating with Colleague objects.
    """
    def __init__( self,name='边防处理中心'):
        super(FrontierDealCenter,self).__init__(name)
        self.ls=list()
        pass
    def Register(self,sentry):
        self.ls.append(sentry)
        pass

    def Request(self, sentry):
        print('#############################')
        print(self.name+':')
        print('   收到信息：'+sentry.info+ '  来源：' +sentry.name)
        print('   处理：请其它小队配合')
        
        print('\n')
        sentry.Recieve('已派其它小队配合你部')
        print('\n')
        
        for obj in self.ls:
            if obj!=sentry:
                obj.Recieve('请迅速配合'+sentry.name)
                pass
            pass
        pass

class Sentry(object):
    """Each colleague class knows its mediator object and communicates with its
    mediator whenever it would have otherwise communicated with another colleague.
    """
    m_Headquarters= Headquarters()

    def __init__(self, name):
        self.info=None
        self.mediator=None
        self.name=name
        pass

    def Recieve(self, info):
        print(self.name+':')
        print('   收到信息：'+info)
        pass

    def Send(self,mediator):
        pass
    
    def Register(self,mediator):
        self.mediator=mediator
        pass    

class SentryA(Sentry):
    """Each colleague class knows its mediator object and communicates with its
    mediator whenever it would have otherwise communicated with another colleague.
    """
    m_FrontierDealCenter= FrontierDealCenter()

    def __init__(self, name='警犬巡逻队'):
        super(SentryA,self).__init__(name)
        pass

    def Send(self):
        self.info='发现可疑物品'
        self.mediator.Request(self)
        pass

class SentryB(Sentry):
    """Each colleague class knows its mediator object and communicates with its
    mediator whenever it would have otherwise communicated with another colleague.
    """
    m_FrontierDealCenter= FrontierDealCenter()

    def __init__(self, name='边境情报队'):
        super(SentryB,self).__init__(name)

        
    def Send(self):
        self.info='四点整，边境将有可疑组织活动'
        self.mediator.Request(self)        
        pass

class SentryC(Sentry):
    """Each colleague class knows its mediator object and communicates with its
    mediator whenever it would have otherwise communicated with another colleague.
    """
    m_FrontierDealCenter= FrontierDealCenter()

    def __init__(self, name='边境缉毒队'):
        super(SentryC,self).__init__(name)

    def Send(self):
        self.info='有毒贩入境'
        self.mediator.Request(self)        
        pass
    
#客户端
if(__name__=="__main__"):
    
    #建立边防事务指挥中心
    m_FrontierDealCenter=FrontierDealCenter()
    
    #成立边防小队
    m_SentryA=SentryA()
    m_SentryB=SentryB()    
    m_SentryC=SentryC()
    
    #在指挥中心注册小队
    m_FrontierDealCenter.Register(m_SentryA)
    m_FrontierDealCenter.Register(m_SentryB)   
    m_FrontierDealCenter.Register(m_SentryC)
    #在各小队注册指挥中心
    
    m_SentryA.Register(m_FrontierDealCenter) 
    m_SentryB.Register(m_FrontierDealCenter)    
    m_SentryC.Register(m_FrontierDealCenter)    
   
    #请求
    m_SentryB.Send()
    m_SentryA.Send()

运行结果：