protected Object getObjectForBeanInstance(
Object beanInstance, String name, String beanName, @Nullable RootBeanDefinition mbd) {

	//  是否是factorybean？ 判断方法为是否以&开头11    Don't let calling code try to dereference the factory if the bean isn't a factory.
	if (BeanFactoryUtils.isFactoryDereference(name)) {
		//nullbean
		if (beanInstance instanceof NullBean) {
			return beanInstance;
		}
		//乱取beanname ?
		if (!(beanInstance instanceof FactoryBean)) {
			throw new BeanIsNotAFactoryException(beanName, beanInstance.getClass());
		}
		if (mbd != null) {
			mbd.isFactoryBean = true;
		}
		return beanInstance;
	}