code: private XAnnotationInvocationHandler asOneOfUs(Object o) {
  		if (Proxy.isProxyClass(o.getClass())) {
  			InvocationHandler handler = Proxy.getInvocationHandler(o);
  			if (handler instanceof XAnnotationInvocationHandler)
  				return (XAnnotationInvocationHandler) handler;
  		}
  		return null;
  	}
docs: Returns an object's invocation handler if that object is a dynamic proxy
  with a handler of type AnnotationInvocationHandler. Returns null
  otherwise.