python:装饰模式的一个实现

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import sys
sys.path.append("..")

import common

class Component:
    def __init__(self,data):
        self.url = data["url"]
        self.noteId = data["noteId"]
        self.userId = data["userId"]
        self.folderId = data["folderId"]
        
    def execute(self):
        pass


class NoteComponent(Component):
    def __init__(self,data,component=None):
        self.component = component
        Component.__init__(self, data)
    
    def setComponent(self,component):
        self.component = component

class HtmlCatcher(NoteComponent):
    def execute(self):
        if self.component != None:
            self.component.execute()
        print self.__class__.__name__

class ImageCatcher(NoteComponent):
    def execute(self):
        if self.component != None:
            self.component.execute()
        print self.__class__.__name__
    
class shareNoteComponet(NoteComponent):
    def execute(self):
        if self.component != None:
            self.component.execute()
        print self.__class__.__name__
    
def process(message):
    component = None
    if message['TYPE'] & common.CATCH_PAGE:
        component = HtmlCatcher(message["DATA"])
        
    if message['TYPE'] & common.CATCH_IMAGE:
        component1 = ImageCatcher(message["DATA"])
        component1.setComponent(component)
        component = component1
        
    if message['TYPE'] & common.SAVE_SHARED:
        component1 = shareNoteComponet(message["DATA"])
        component1.setComponent(component)
        component = component1
    
    component.execute()
        


if __name__ == "__main__":

    message = {
            #"TYPE":common.CATCH_PAGE,
            #"TYPE":common.CATCH_IMAGE | common.SAVE_SHARED,
            "TYPE":common.CATCH_PAGE | common.SAVE_SHARED | common.CATCH_IMAGE,
            "DATA":
                {
                    "url":"http://www.baidu.com",
                    "noteId":100,
                    "userId":100,
                    "folderId":100,
                }
    }
    
    process(message)