实现这两个listener都可以进行自己的初始化逻辑。

InitializingBean.afterPropertiesSet 这个优先调用

ApplicationListener.onApplicationEvent 这个后调用 他们分别由 AbstractApplicationContext.refresh 方法

调用的如下两个函数调用到的：

finishBeanFactoryInitialization(beanFactory);

finishRefresh();

public class InitListener implements ApplicationListener, InitializingBean {
      @Resource     private AboutDao aboutDao;     @Override     public void afterPropertiesSet() throws Exception {
          System.out.println("afterPropertiesSet");         Integer count = 0;         try {
              count = aboutDao.count();         } catch (Exception e) {
              e.printStackTrace();         }         System.out.println(count);     }     @Override     public void onApplicationEvent(ApplicationEvent event) {
          //防止重复调用         ApplicationContext ctx = (ApplicationContext) event.getSource();         if (ctx.getParent() != null) {
              return;         }         System.out.println("onApplicationEvent");         Integer count = 0;         try {
              count = aboutDao.count();         } catch (Exception e) {
              e.printStackTrace();         }         System.out.println(count);     } }