Spring 得到FactoryBean

查看源码：

		// Now we have the bean instance, which may be a normal bean or a FactoryBean.
		// If it's a FactoryBean, we use it to create a bean instance, unless the
		// caller actually wants a reference to the factory.
		if (!(beanInstance instanceof FactoryBean) || BeanFactoryUtils.isFactoryDereference(name)) {
			return beanInstance;
		}

	/**
	 * Return whether the given name is a factory dereference
	 * (beginning with the factory dereference prefix).
	 * @param name the name of the bean
	 * @return whether the given name is a factory dereference
	 * @see BeanFactory#FACTORY_BEAN_PREFIX
	 */
	public static boolean isFactoryDereference(String name) {
		return (name != null && name.startsWith(BeanFactory.FACTORY_BEAN_PREFIX));
	}

String FACTORY_BEAN_PREFIX = "&";

所以很简单，只要beanname 之前加上了&符号就会直接返回该FactoryBean