java - Spring：SmartLifecycle：Lifecycle.stop() 未调用但它与@EnableWebMvc

Question

当我使用 java config 但不使用 XML config 进行配置时，我无法弄清楚为什么我在 Tomcat 中运行的简单 Spring 5.1.12 webapp 调用 Lifecycle.stop() 方法。我有问题中的 bean LifecycleLoggingBean 实现 SmartLifecycle 并且我已经覆盖了所有方法（见问题结尾）。

更新：如果我在 mvc-servlet.xml 中实例化我的 LifecycleLoggingBean ，则调用 stop 。我想默认情况下没有什么能阻止主应用程序上下文。是否有一种“正确”的方式来触发主应用程序上下文的关闭？事实证明，它也是从主应用程序上下文中调用的，只是没有记录。

如果我像这样配置应用程序，则会调用 Lifecycle.stop()：

@EnableWebMvc
@Configuration
@ComponentScan({"some.package"})
public class SpringConfig implements WebMvcConfigurer {

    @Bean
    public InternalResourceViewResolver viewResolver() {
        InternalResourceViewResolver viewResolver
                = new InternalResourceViewResolver();
        viewResolver.setViewClass(JstlView.class);
        viewResolver.setPrefix("/WEB-INF/views/");
        viewResolver.setSuffix(".jsp");
        return viewResolver;
    }
}

如果我删除该类，而是将以下内容放入 web.xml：

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

<servlet>
    <servlet-name>mvc</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>2</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>mvc</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>

以及 applicationContext.xml 中的以下内容：

<context:component-scan base-package="some.package" />
<mvc:annotation-driven />

<bean class = "org.springframework.web.servlet.view.InternalResourceViewResolver">
   <property name = "prefix" value = "/WEB-INF/jsp/"/>
   <property name = "suffix" value = ".jsp"/>
</bean>

并添加一个 mvc-servlet.xml：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
            http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
            ">
</beans>

然后 Lifecycle.stop() 不被调用。

在所有情况下，都会调用 Lifecycle.start()。

以下是带有 Java 配置的日志：

[org.springframework.web.servlet.DispatcherServlet]:525  -  - Initializing Servlet 'dispatcher'
[some.packge.testapp.LifecycleLoggingBean]:15   -  - ********** SmartLifecycle isAutoStartup
[some.packge.testapp.LifecycleLoggingBean]:21   -  - ********** SmartLifecycle getPhase
[some.packge.testapp.LifecycleLoggingBean]:43   -  - ********** Lifecycle isRunning false
[some.packge.testapp.LifecycleLoggingBean]:15   -  - ********** SmartLifecycle isAutoStartup
[some.packge.testapp.LifecycleLoggingBean]:27   -  - ********** Lifecycle start
[org.springframework.web.servlet.DispatcherServlet]:547  -  - Completed initialization in 953 ms
[some.packge.testapp.LifecycleLoggingBean]:21   -  - ********** SmartLifecycle getPhase
[some.packge.testapp.LifecycleLoggingBean]:43   -  - ********** Lifecycle isRunning true
[some.packge.testapp.LifecycleLoggingBean]:32   -  - ********** SmartLifecycle stop
[some.packge.testapp.LifecycleLoggingBean]:39   -  - ********** Lifecycle stop

以下是带有 xml 配置的日志：

[org.springframework.web.context.ContextLoader]:271  -  - Root WebApplicationContext: initialization started
[some.package.testapp.LifecycleLoggingBean]:15   -  - ********** SmartLifecycle isAutoStartup
[some.package.testapp.LifecycleLoggingBean]:21   -  - ********** SmartLifecycle getPhase
[some.package.testapp.LifecycleLoggingBean]:43   -  - ********** Lifecycle isRunning false
[some.package.testapp.LifecycleLoggingBean]:15   -  - ********** SmartLifecycle isAutoStartup
[some.package.testapp.LifecycleLoggingBean]:27   -  - ********** Lifecycle start
[org.springframework.web.context.ContextLoader]:307  -  - Root WebApplicationContext initialized in 1203 ms
[org.springframework.web.servlet.DispatcherServlet]:525  -  - Initializing Servlet 'dispatcher'
[org.springframework.web.servlet.DispatcherServlet]:547  -  - Completed initialization in 31 ms
[org.springframework.web.servlet.DispatcherServlet]:525  -  - Initializing Servlet 'mvc'
[org.springframework.web.servlet.DispatcherServlet]:547  -  - Completed initialization in 31 ms

这是 LifecycleLoggingBean：

@Component
public class LifecycleLoggingBean implements SmartLifecycle {
    private final Logger logger = LoggerFactory.getLogger(LifecycleLoggingBean.class);
    @Override
    public boolean isAutoStartup() {
        logger.info("********** SmartLifecycle isAutoStartup");
        return true;
    }
    @Override
    public int getPhase() {
        // start last and stop first
        logger.info("********** SmartLifecycle getPhase");
        return Integer.MAX_VALUE;
    }
    private AtomicBoolean isRunning = new AtomicBoolean(false);
    @Override
    public void start() {
        logger.info("********** Lifecycle start");
        isRunning.set(true);
    }
    @Override
    public void stop(Runnable callback) {
        logger.info("********** SmartLifecycle stop");
        stop();
        callback.run();
    }
    @Override
    public void stop() {
        isRunning.set(false);
        logger.info("********** Lifecycle stop");
    }
    public boolean isRunning() {
        boolean rval = isRunning.get();
        logger.info("********** Lifecycle isRunning {}", rval);
        return rval;
    }
}

标签： javaspringspring-mvc

Answer 1

事实证明，stop() 方法也是从主应用程序上下文调用的，只是没有记录。Log4j2自动将自己注册为 Web 片段，这意味着它在 ContextLoaderListener 的 contextDestroyed 方法被调用之前被关闭。当最终调用 contextDestroyed 时，日志消息会丢失。但是，通过登录到 System.out，我能够看到 tomcat 日志中的消息。

通过禁用 log4j 的正常自动注册并以旧的（servlet 2.5 及之前）方式注册它，我能够显示日志消息。

<context-param>
    <param-name>isLog4jAutoInitializationDisabled</param-name>
    <param-value>true</param-value>
</context-param>

<listener>
    <listener-class>org.apache.logging.log4j.web.Log4jServletContextListener</listener-class>
</listener>

<filter>
    <filter-name>log4jServletFilter</filter-name>
    <filter-class>org.apache.logging.log4j.web.Log4jServletFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>log4jServletFilter</filter-name>
    <url-pattern>/*</url-pattern>
    <dispatcher>REQUEST</dispatcher>
    <dispatcher>FORWARD</dispatcher>
    <dispatcher>INCLUDE</dispatcher>
    <dispatcher>ERROR</dispatcher>
    <!-- Servlet 3.0 w/ disabled auto-initialization only; not supported in 2.5 -->
    <dispatcher>ASYNC</dispatcher>
</filter-mapping>

这最终成为了一个次优的解决方案，因为我们的日志基础设施依赖于使用Web 查找${web:servletContextName}，它似乎没有在默认注册之外进行初始化。所以我们将使用@EventListener 而不是SmartLifecycle。

@EventListener(classes = {
        ContextStoppedEvent.class,
        ContextClosedEvent.class
})
public void stop() {
    // still get to clean up.
}

log4j 问题跟踪器中有一个未解决的问题准确描述了这个问题： https ://issues.apache.org/jira/browse/LOG4J2-2624