java - Spring Boot 关闭钩子(Hook)

Question

如何注册/添加一个自定义关闭例程，该例程在我的 Spring Boot 应用程序关闭时触发？

场景:我将 Spring Boot 应用程序部署到 Jetty servlet 容器(即，没有嵌入式 Jetty)。我的应用程序使用 Logback 进行日志记录，我想在运行时使用 Logback 的 MBean JMX 配置器更改日志记录级别。 Its documentation states that to avoid memory leaks, on shutdown a specific LoggerContext shutdown method has to be called .

监听 Spring Boot 关闭事件的好方法是什么？

我试过了:

public static void main(String[] args) throws Exception {
    ConfigurableApplicationContext cac = SpringApplication.run(Example.class, args);

    cac.addApplicationListener(new ApplicationListener<ContextClosedEvent>() {

        @Override
        public void onApplicationEvent(ContextClosedEvent event) {
            logger.info("Do something");
        }
    });
}

但是当应用程序关闭时，这个注册的监听器不会被调用。

Answer 1

https://docs.spring.io/spring-boot/docs/current-SNAPSHOT/reference/htmlsingle/#features.spring-application.application-exit

Each SpringApplication will register a shutdown hook with the JVM to ensure that the ApplicationContext is closed gracefully on exit. All the standard Spring lifecycle callbacks (such as the DisposableBean interface, or the @PreDestroy annotation) can be used.

In addition, beans may implement the org.springframework.boot.ExitCodeGenerator interface if they wish to return a specific exit code when the application ends.