Spring中SmartLifecycle和Lifecycle的作用和区别

startBeans:142, DefaultLifecycleProcessor (org.springframework.context.support)
onRefresh:123, DefaultLifecycleProcessor (org.springframework.context.support)
finishRefresh:934, AbstractApplicationContext (org.springframework.context.support)
refresh:585, AbstractApplicationContext (org.springframework.context.support)
refresh:144, ServletWebServerApplicationContext (org.springframework.boot.web.servlet.context)
refresh:755, SpringApplication (org.springframework.boot)
refreshContext:426, SpringApplication (org.springframework.boot)
run:326, SpringApplication (org.springframework.boot)
run:1299, SpringApplication (org.springframework.boot)
run:1288, SpringApplication (org.springframework.boot)
main:31, DemoApplication (com.example.demo)

@Override
public void onRefresh() {
	startBeans(true); //autoStartupOnly = true
	this.running = true;
}

private void startBeans(boolean autoStartupOnly) {
	Map<String, Lifecycle> lifecycleBeans = getLifecycleBeans();
	Map<Integer, LifecycleGroup> phases = new TreeMap<>();

	lifecycleBeans.forEach((beanName, bean) -> {
		if (!autoStartupOnly || (bean instanceof SmartLifecycle && ((SmartLifecycle) bean).isAutoStartup())) {
			int phase = getPhase(bean);
			phases.computeIfAbsent(phase, p -> 
			 new LifecycleGroup(phase, this.timeoutPerShutdownPhase, lifecycleBeans, autoStartupOnly)
			).add(beanName, bean);
		}
	});
	if (!phases.isEmpty()) {
		phases.values().forEach(LifecycleGroup::start);
	}
}

@Override
public void registerShutdownHook() {
	if (this.shutdownHook == null) {
		// No shutdown hook registered yet.
		this.shutdownHook = new Thread(SHUTDOWN_HOOK_THREAD_NAME) {
			@Override
			public void run() {
				synchronized (startupShutdownMonitor) {
					doClose();
				}
			}
		};
		Runtime.getRuntime().addShutdownHook(this.shutdownHook);
	}
}

/**
 * {@link EnableAutoConfiguration Auto-configuration} relating to the application
 * context's lifecycle.
 *
 * @author Andy Wilkinson
 * @since 2.3.0
 */
@Configuration(proxyBeanMethods = false)
@EnableConfigurationProperties(LifecycleProperties.class)
public class LifecycleAutoConfiguration {

	@Bean(name = AbstractApplicationContext.LIFECYCLE_PROCESSOR_BEAN_NAME)
	@ConditionalOnMissingBean(name = AbstractApplicationContext.LIFECYCLE_PROCESSOR_BEAN_NAME,
			search = SearchStrategy.CURRENT)
	public DefaultLifecycleProcessor defaultLifecycleProcessor(LifecycleProperties properties) {
		DefaultLifecycleProcessor lifecycleProcessor = new DefaultLifecycleProcessor();
		lifecycleProcessor.setTimeoutPerShutdownPhase(properties.getTimeoutPerShutdownPhase().toMillis());
		return lifecycleProcessor;
	}
}

@Override
protected void onRefresh() {
	super.onRefresh();
	try {
		createWebServer();
	}catch (Throwable ex) {
		throw new ApplicationContextException("Unable to start web server", ex);
	}
}

private void createWebServer() {
	WebServer webServer = this.webServer;
	ServletContext servletContext = getServletContext();
	if (webServer == null && servletContext == null) {
		StartupStep createWebServer = this.getApplicationStartup().start("spring.boot.webserver.create");
		ServletWebServerFactory factory = getWebServerFactory();
		createWebServer.tag("factory", factory.getClass().toString());
		this.webServer = factory.getWebServer(getSelfInitializer());
		createWebServer.end();
		getBeanFactory().registerSingleton("webServerGracefulShutdown",
				new WebServerGracefulShutdownLifecycle(this.webServer));
		getBeanFactory().registerSingleton("webServerStartStop",
				new WebServerStartStopLifecycle(this, this.webServer));
	}
	else if (servletContext != null) {
		try {
			getSelfInitializer().onStartup(servletContext);
		}
		catch (ServletException ex) {
			throw new ApplicationContextException("Cannot initialize servlet context", ex);
		}
	}
	initPropertySources();
}

class WebServerStartStopLifecycle implements SmartLifecycle {

	private final ServletWebServerApplicationContext applicationContext;
	private final WebServer webServer;
	private volatile boolean running;

	WebServerStartStopLifecycle(ServletWebServerApplicationContext applicationContext, WebServer webServer) {
		this.applicationContext = applicationContext;
		this.webServer = webServer;
	}

	@Override
	public void start() {
		this.webServer.start();
		this.running = true;
		this.applicationContext
				.publishEvent(new ServletWebServerInitializedEvent(this.webServer, this.applicationContext));
	}

	@Override
	public void stop() { this.webServer.stop(); }

	@Override
	public boolean isRunning() {	return this.running; }

	@Override
	public int getPhase() { return Integer.MAX_VALUE - 1; }
}