abstractapplicationcontext.java

来自「spring framework 2.5.4源代码」· Java 代码 · 共 1,206 行 · 第 1/4 页

			String postProcessorName = (String) it.next();
			nonOrderedPostProcessors.add(getBean(postProcessorName));
		}
		registerBeanPostProcessors(beanFactory, nonOrderedPostProcessors);
	}

	/**
	 * Register the given BeanPostProcessor beans.
	 */
	private void registerBeanPostProcessors(ConfigurableListableBeanFactory beanFactory, List postProcessors) {
		for (Iterator it = postProcessors.iterator(); it.hasNext();) {
			BeanPostProcessor postProcessor = (BeanPostProcessor) it.next();
			beanFactory.addBeanPostProcessor(postProcessor);
		}
	}

	/**
	 * Initialize the MessageSource.
	 * Use parent's if none defined in this context.
	 */
	protected void initMessageSource() {
		ConfigurableListableBeanFactory beanFactory = getBeanFactory();
		if (beanFactory.containsLocalBean(MESSAGE_SOURCE_BEAN_NAME)) {
			this.messageSource = (MessageSource) beanFactory.getBean(MESSAGE_SOURCE_BEAN_NAME, MessageSource.class);
			// Make MessageSource aware of parent MessageSource.
			if (this.parent != null && this.messageSource instanceof HierarchicalMessageSource) {
				HierarchicalMessageSource hms = (HierarchicalMessageSource) this.messageSource;
				if (hms.getParentMessageSource() == null) {
					// Only set parent context as parent MessageSource if no parent MessageSource
					// registered already.
					hms.setParentMessageSource(getInternalParentMessageSource());
				}
			}
			if (logger.isDebugEnabled()) {
				logger.debug("Using MessageSource [" + this.messageSource + "]");
			}
		}
		else {
			// Use empty MessageSource to be able to accept getMessage calls.
			DelegatingMessageSource dms = new DelegatingMessageSource();
			dms.setParentMessageSource(getInternalParentMessageSource());
			this.messageSource = dms;
			beanFactory.registerSingleton(MESSAGE_SOURCE_BEAN_NAME, this.messageSource);
			if (logger.isDebugEnabled()) {
				logger.debug("Unable to locate MessageSource with name '" + MESSAGE_SOURCE_BEAN_NAME +
						"': using default [" + this.messageSource + "]");
			}
		}
	}

	/**
	 * Initialize the ApplicationEventMulticaster.
	 * Uses SimpleApplicationEventMulticaster if none defined in the context.
	 * @see org.springframework.context.event.SimpleApplicationEventMulticaster
	 */
	protected void initApplicationEventMulticaster() {
		ConfigurableListableBeanFactory beanFactory = getBeanFactory();
		if (beanFactory.containsLocalBean(APPLICATION_EVENT_MULTICASTER_BEAN_NAME)) {
			this.applicationEventMulticaster = (ApplicationEventMulticaster)
					beanFactory.getBean(APPLICATION_EVENT_MULTICASTER_BEAN_NAME, ApplicationEventMulticaster.class);
			if (logger.isDebugEnabled()) {
				logger.debug("Using ApplicationEventMulticaster [" + this.applicationEventMulticaster + "]");
			}
		}
		else {
			this.applicationEventMulticaster = new SimpleApplicationEventMulticaster();
			beanFactory.registerSingleton(APPLICATION_EVENT_MULTICASTER_BEAN_NAME, this.applicationEventMulticaster);
			if (logger.isDebugEnabled()) {
				logger.debug("Unable to locate ApplicationEventMulticaster with name '" +
						APPLICATION_EVENT_MULTICASTER_BEAN_NAME +
						"': using default [" + this.applicationEventMulticaster + "]");
			}
		}
	}

	/**
	 * Template method which can be overridden to add context-specific refresh work.
	 * Called on initialization of special beans, before instantiation of singletons.
	 * <p>This implementation is empty.
	 * @throws BeansException in case of errors
	 * @see #refresh()
	 */
	protected void onRefresh() throws BeansException {
		// For subclasses: do nothing by default.
	}

	/**
	 * Add beans that implement ApplicationListener as listeners.
	 * Doesn't affect other listeners, which can be added without being beans.
	 */
	protected void registerListeners() {
		// Register statically specified listeners first.
		for (Iterator it = getApplicationListeners().iterator(); it.hasNext();) {
			addListener((ApplicationListener) it.next());
		}
		// Do not initialize FactoryBeans here: We need to leave all regular beans
		// uninitialized to let post-processors apply to them!
		Collection listenerBeans = getBeansOfType(ApplicationListener.class, true, false).values();
		for (Iterator it = listenerBeans.iterator(); it.hasNext();) {
			addListener((ApplicationListener) it.next());
		}
	}

	/**
	 * Subclasses can invoke this method to register a listener.
	 * Any beans in the context that are listeners are automatically added.
	 * @param listener the listener to register
	 */
	protected void addListener(ApplicationListener listener) {
		getApplicationEventMulticaster().addApplicationListener(listener);
	}

	/**
	 * Finish the initialization of this context's bean factory,
	 * initializing all remaining singleton beans.
	 */
	protected void finishBeanFactoryInitialization(ConfigurableListableBeanFactory beanFactory) {
		// Stop using the temporary ClassLoader for type matching.
		beanFactory.setTempClassLoader(null);

		// Allow for caching all bean definition metadata, not expecting further changes.
		beanFactory.freezeConfiguration();

		// Instantiate all remaining (non-lazy-init) singletons.
		beanFactory.preInstantiateSingletons();
	}

	/**
	 * Finish the refresh of this context, publishing the
	 * {@link org.springframework.context.event.ContextRefreshedEvent}.
	 */
	protected void finishRefresh() {
		publishEvent(new ContextRefreshedEvent(this));
	}

	/**
	 * Cancel this context's refresh attempt, resetting the <code>active</code> flag
	 * after an exception got thrown.
	 * @param ex the exception that led to the cancellation
	 */
	protected void cancelRefresh(BeansException ex) {
		synchronized (this.activeMonitor) {
			this.active = false;
		}
	}


	/**
	 * Register a shutdown hook with the JVM runtime, closing this context
	 * on JVM shutdown unless it has already been closed at that time.
	 * <p>Delegates to <code>doClose()</code> for the actual closing procedure.
	 * @see java.lang.Runtime#addShutdownHook
	 * @see #close()
	 * @see #doClose()
	 */
	public void registerShutdownHook() {
		if (this.shutdownHook == null) {
			// No shutdown hook registered yet.
			this.shutdownHook = new Thread() {
				public void run() {
					doClose();
				}
			};
			Runtime.getRuntime().addShutdownHook(this.shutdownHook);
		}
	}

	/**
	 * DisposableBean callback for destruction of this instance.
	 * Only called when the ApplicationContext itself is running
	 * as a bean in another BeanFactory or ApplicationContext,
	 * which is rather unusual.
	 * <p>The <code>close</code> method is the native way to
	 * shut down an ApplicationContext.
	 * @see #close()
	 * @see org.springframework.beans.factory.access.SingletonBeanFactoryLocator
	 */
	public void destroy() {
		close();
	}

	/**
	 * Close this application context, destroying all beans in its bean factory.
	 * <p>Delegates to <code>doClose()</code> for the actual closing procedure.
	 * Also removes a JVM shutdown hook, if registered, as it's not needed anymore.
	 * @see #doClose()
	 * @see #registerShutdownHook()
	 */
	public void close() {
		synchronized (this.startupShutdownMonitor) {
			doClose();
			// If we registered a JVM shutdown hook, we don't need it anymore now:
			// We've already explicitly closed the context.
			if (this.shutdownHook != null) {
				Runtime.getRuntime().removeShutdownHook(this.shutdownHook);
			}
		}
	}

	/**
	 * Actually performs context closing: publishes a ContextClosedEvent and
	 * destroys the singletons in the bean factory of this application context.
	 * <p>Called by both <code>close()</code> and a JVM shutdown hook, if any.
	 * @see org.springframework.context.event.ContextClosedEvent
	 * @see org.springframework.beans.factory.config.ConfigurableBeanFactory#destroySingletons()
	 * @see #close()
	 * @see #registerShutdownHook()
	 */
	protected void doClose() {
		if (isActive()) {
			if (logger.isInfoEnabled()) {
				logger.info("Closing " + this);
			}
			try {
				// Publish shutdown event.
				publishEvent(new ContextClosedEvent(this));
			}
			catch (Throwable ex) {
				logger.error("Exception thrown from ApplicationListener handling ContextClosedEvent", ex);
			}
			// Stop all Lifecycle beans, to avoid delays during individual destruction.
			Map lifecycleBeans = getLifecycleBeans();
			for (Iterator it = new LinkedHashSet(lifecycleBeans.keySet()).iterator(); it.hasNext();) {
				String beanName = (String) it.next();
				doStop(lifecycleBeans, beanName);
			}
			// Destroy all cached singletons in the context's BeanFactory.
			destroyBeans();
			// Close the state of this context itself.
			closeBeanFactory();
			onClose();
			synchronized (this.activeMonitor) {
				this.active = false;
			}
		}
	}

	/**
	 * Template method for destroying all beans that this context manages.
	 * The default implementation destroy all cached singletons in this context,
	 * invoking <code>DisposableBean.destroy()</code> and/or the specified
	 * "destroy-method".
	 * <p>Can be overridden to add context-specific bean destruction steps
	 * right before or right after standard singleton destruction,
	 * while the context's BeanFactory is still active.
	 * @see #getBeanFactory()
	 * @see org.springframework.beans.factory.config.ConfigurableBeanFactory#destroySingletons()
	 */
	protected void destroyBeans() {
		getBeanFactory().destroySingletons();
	}

	/**
	 * Template method which can be overridden to add context-specific shutdown work.
	 * The default implementation is empty.
	 * <p>Called at the end of {@link #doClose}'s shutdown procedure, after
	 * this context's BeanFactory has been closed. If custom shutdown logic
	 * needs to execute while the BeanFactory is still active, override
	 * the {@link #destroyBeans()} method instead.
	 */
	protected void onClose() {
		// For subclasses: do nothing by default.
	}

	public boolean isActive() {
		synchronized (this.activeMonitor) {
			return this.active;
		}
	}


	//---------------------------------------------------------------------
	// Implementation of BeanFactory interface
	//---------------------------------------------------------------------

	public Object getBean(String name) throws BeansException {
		return getBeanFactory().getBean(name);
	}

	public Object getBean(String name, Class requiredType) throws BeansException {
		return getBeanFactory().getBean(name, requiredType);
	}

	public Object getBean(String name, Object[] args) throws BeansException {
		return getBeanFactory().getBean(name, args);
	}

	public boolean containsBean(String name) {
		return getBeanFactory().containsBean(name);
	}

	public boolean isSingleton(String name) throws NoSuchBeanDefinitionException {
		return getBeanFactory().isSingleton(name);
	}

	public boolean isPrototype(String name) throws NoSuchBeanDefinitionException {
		return getBeanFactory().isPrototype(name);
	}

	public boolean isTypeMatch(String name, Class targetType) throws NoSuchBeanDefinitionException {
		return getBeanFactory().isTypeMatch(name, targetType);
	}