python实现Composite模式

待我称王封你为后i 2022-03-20 01:18 74阅读 0赞

\#-\*-coding:utf-8-\*-  
  
'''  
意图：将一个复杂对象的构建与它的表示分离，使得同样的构建过程可以创建不同的表示  
'''  
from abc import ABCMeta  
  
class Component():  
    \_\_metaclass\_\_ = ABCMeta  
    def \_\_init\_\_(self):  
        pass  
    def operation(self):  
        pass  
    def add(self, com):  
        if not isinstance(comp, Component):  
            raise 'add method first argument shuld be a instance of Component!'  
          
    def remove(self, comp):  
        if not isinstance(comp, Component):  
            raise 'remove method first argument shuld be a instance of Component!'  
          
    def getChild(self, index):  
        if not isinstance(index, int):  
            raise 'getChild method first argument should be int type!'  
      
class Composite(Component):  
    compList = \[\]  
    def operation(self):  
        for comp in tuple(self.compList):  
            comp.operation()  
              
    def add(self, comp):  
        if not isinstance(comp, Component):  
            raise 'add method first argument shuld be a instance of Component!'  
        self.compList.append(comp)  
          
    def remove(self, comp):  
        if not isinstance(comp, Component):  
            raise 'remove method first argument shuld be a instance of Component!'  
        index = None  
\#        try:  
\#            index = self.compList.index(comp)  
\#        except:  
\#            raise "comp does't exists"  
        \#不用上面的,用index中的except机制，减少try使用耗时间  
        index = self.compList.index(comp)  
        if index is not None:  
            del self.compList\[index\]  
    def getChild(self, index):  
        if not isinstance(index, int):  
            raise 'getChild method first argument should be int type!'  
        return self.compList\[index\]  
  
class Leaf(Component):  
    def operation(self):  
        print 'Leaf operation...'  
  
  
if \_\_name\_\_ == "\_\_main\_\_":  
     leaf = Leaf()  
     leaf.operation()  
       
     composite = Composite()  
     composite.add(leaf)  
     composite.operation()  
       
     leaf1 = composite.getChild(0)  
     leaf1.operation()