spring boot 监听容器启动代码实例

@Component
public class MyApplicationListener implements ApplicationListener<ContextRefreshedEvent> {

  @Override
  public void onApplicationEvent(ContextRefreshedEvent contextRefreshedEvent) {

    // 获取spring 上下文
    ApplicationContext applicationContext = contextRefreshedEvent.getApplicationContext();

    // do your work...
}

// 遍历所有ApplicationListeners, 依次执行ApplicationListener 的onApplicationEvent()方法
public void multicastEvent(ApplicationEvent event, @Nullable ResolvableType eventType) {
  ResolvableType type = eventType != null ? eventType : this.resolveDefaultEventType(event);
  Iterator var4 = this.getApplicationListeners(event, type).iterator();

  while(var4.hasNext()) {
    ApplicationListener<?> listener = (ApplicationListener)var4.next();
    Executor executor = this.getTaskExecutor();
    if (executor != null) {
      executor.execute(() -> {
        this.invokeListener(listener, event);
      });
    } else {
      this.invokeListener(listener, event);
    }
  }

}