python实现反射功能
By:Roy.LiuLast updated:2012-02-16
在java中用classfor 很容易实现反射,比如SPRING,就大量用这个东西实现。现在用python做服务端,也想用类似的方式。在搜索了大量的网站后,找到一个classloader方案,源代码,例子如下。
''' Created on 2012-2-16 @author: Administrator ''' import sys, types,new def _get_mod(modulePath): try: aMod = sys.modules[modulePath] if not isinstance(aMod, types.ModuleType): raise KeyError except KeyError: # The last [''] is very important! aMod = __import__(modulePath, globals(), locals(), ['']) sys.modules[modulePath] = aMod return aMod def _get_func(fullFuncName): """Retrieve a function object from a full dotted-package name.""" # Parse out the path, module, and function lastDot = fullFuncName.rfind(u".") funcName = fullFuncName[lastDot + 1:] modPath = fullFuncName[:lastDot] aMod = _get_mod(modPath) aFunc = getattr(aMod, funcName) # Assert that the function is a *callable* attribute. assert callable(aFunc), u"%s is not callable." % fullFuncName # Return a reference to the function itself, # not the results of the function. return aFunc def _get_Class(fullClassName, parentClass=None): """Load a module and retrieve a class (NOT an instance). If the parentClass is supplied, className must be of parentClass or a subclass of parentClass (or None is returned). """ aClass = _get_func(fullClassName) # Assert that the class is a subclass of parentClass. if parentClass is not None: if not issubclass(aClass, parentClass): raise TypeError(u"%s is not a subclass of %s" % (fullClassName, parentClass)) # Return a reference to the class itself, not an instantiated object. return aClass def applyFuc(obj,strFunc,arrArgs): objFunc = getattr(obj, strFunc) return apply(objFunc,arrArgs) def getObject(fullClassName): clazz = _get_Class(fullClassName) return clazz() if __name__=='__main__': aa=getObject("inetservices.services.company.Company") bb=applyFuc(aa, "select", ['select * from ngsys2',None]) print bb
From:一号门
Previous:献给情人节
COMMENTS