python中反射用法实例

import sys, types,newdef _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 aModdef _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 aFuncdef _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 aClassdef 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