@Override
    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
        return bean;
    }
Spring {@link BeanPostProcessor} that detects, {@link EventBusAware} and classes containing
{@link Subscribe @Subscribe} methods. Any classes implementing EventBusAware will have the setEventBus() method
called with the <code>eventBus</code>. Any classes discovered with methods that are annotated
with @Subscribe will be automatically registered with the EventBus.

<p><strong>NOTE:</strong> in a Spring environment implementing EventBusAware is not necessary,
as you can just inject the EventBus with {@link org.springframework.beans.factory.annotation.Autowire @Autowire}.</p>

@see EventBusAware
@see Subscribe
@since 1.4
support/spring/src/main/java/org/apache/shiro/spring/ShiroEventBusBeanPostProcessor.java