Python 责任链模式实现

# -*- coding: utf-8 -*-
"""
Created on Mon Feb 26 11:45:46 2018

@author: mz
"""

class Handler(object):
def __init__(self):
self.handler = None

def Handle(self):
pass

def NextHandler(self, rhs):
self.handler = rhs

class Boss(Handler):
def Handle(self):
print("Boss handle")
if self.handler is not None:
self.handler.Handle()

class Derector(Handler):
def Handle(self):
print("Derector handle ->")
if self.handler is not None:
self.handler.Handle()

class Manager(Handler):
def Handle(self):
print("Manager handle ->")
if self.handler is not None:
self.handler.Handle()

class Employee(Handler):
def Handle(self):
print("Employee handle a request->")
if self.handler is not None:
self.handler.Handle()

if "__main__" == __name__:
employee = Employee()
manager = Manager()

employee.NextHandler(manager)

derector = Derector()
manager.NextHandler(derector)

boss = Boss()
derector.NextHandler(boss)

employee.Handle()

可以看到，设定职责链路后，一旦员工提交申请，业务就会按照流程进行。运行结果如下：Employee handle a request->
Manager handle ->
Derector handle ->
Boss handle