spring启动过程之源码跟踪（中）--spring Debug

上节我们debug到

// Tell the subclass to refresh the internal bean factory.
2 ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory();

我们继续debug 下一步：配置beanfactory的上下文

    /**
     * Configure the factory's standard context characteristics,
     * such as the context's ClassLoader and post-processors.
     * @param beanFactory the BeanFactory to configure
     */
    protected void prepareBeanFactory(ConfigurableListableBeanFactory beanFactory) {
        // Tell the internal bean factory to use the context's class loader.
        beanFactory.setBeanClassLoader(getClassLoader());

        // Populate the bean factory with context-specific resource editors.
        beanFactory.addPropertyEditorRegistrar(new ResourceEditorRegistrar(this));

        // Configure the bean factory with context callbacks.
        beanFactory.addBeanPostProcessor(new ApplicationContextAwareProcessor(this));
        beanFactory.ignoreDependencyInterface(ResourceLoaderAware.class);
        beanFactory.ignoreDependencyInterface(ApplicationEventPublisherAware.class);
        beanFactory.ignoreDependencyInterface(MessageSourceAware.class);
        beanFactory.ignoreDependencyInterface(ApplicationContextAware.class);

        // BeanFactory interface not registered as resolvable type in a plain factory.
        // MessageSource registered (and found for autowiring) as a bean.
        beanFactory.registerResolvableDependency(BeanFactory.class, beanFactory);
        beanFactory.registerResolvableDependency(ResourceLoader.class, this);
        beanFactory.registerResolvableDependency(ApplicationEventPublisher.class, this);
        beanFactory.registerResolvableDependency(ApplicationContext.class, this);

        // Detect a LoadTimeWeaver and prepare for weaving, if found.
        if (beanFactory.containsBean(LOAD_TIME_WEAVER_BEAN_NAME) && JdkVersion.isAtLeastJava15()) {
            // Register the (JDK 1.5 specific) LoadTimeWeaverAwareProcessor.
            try {
                Class ltwapClass = ClassUtils.forName(
                        "org.springframework.context.weaving.LoadTimeWeaverAwareProcessor",
                        AbstractApplicationContext.class.getClassLoader());
                BeanPostProcessor ltwap = (BeanPostProcessor) BeanUtils.instantiateClass(ltwapClass);
                ((BeanFactoryAware) ltwap).setBeanFactory(beanFactory);
                beanFactory.addBeanPostProcessor(ltwap);
            }
            catch (ClassNotFoundException ex) {
                throw new IllegalStateException("Spring's LoadTimeWeaverAwareProcessor class is not available");
            }
            // Set a temporary ClassLoader for type matching.
            beanFactory.setTempClassLoader(new ContextTypeMatchClassLoader(beanFactory.getBeanClassLoader()));
        }
    }

下面是下一步要debug的内容：

                // Allows post-processing of the bean factory in context subclasses.
                postProcessBeanFactory(beanFactory);

                // Invoke factory processors registered as beans in the context.
                invokeBeanFactoryPostProcessors(beanFactory);

                // Register bean processors that intercept bean creation.
                registerBeanPostProcessors(beanFactory);

                // Initialize message source for this context.
                initMessageSource();

                // Initialize event multicaster for this context.
                initApplicationEventMulticaster();

                // Initialize other special beans in specific context subclasses.
                onRefresh();

                // Check for listener beans and register them.
                registerListeners();

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

                // Last step: publish corresponding event.
                finishRefresh();

初始化singletonbean（DefaultListableBeanFactory.java#preInstantiateSingletons()）

    public void preInstantiateSingletons() throws BeansException {
        if (this.logger.isInfoEnabled()) {
            this.logger.info("Pre-instantiating singletons in " + this);
        }

        synchronized (this.beanDefinitionMap) {
            for (Iterator it = this.beanDefinitionNames.iterator(); it.hasNext();) {
                String beanName = (String) it.next();
                RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName);
                if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) {
                    if (isFactoryBean(beanName)) {
                        FactoryBean factory = (FactoryBean) getBean(FACTORY_BEAN_PREFIX + beanName);
                        if (factory instanceof SmartFactoryBean && ((SmartFactoryBean) factory).isEagerInit()) {
                            getBean(beanName);
                        }
                    }
                    else {
                        getBean(beanName);
                    }
                }
            }
        }
    }

结束动作：发布事件

    public void publishEvent(ApplicationEvent event) {
        Assert.notNull(event, "Event must not be null");
        if (logger.isTraceEnabled()) {
            logger.trace("Publishing event in context [" + getId() + "]: " + event);
        }
        getApplicationEventMulticaster().multicastEvent(event);
        if (this.parent != null) {
            this.parent.publishEvent(event);
        }
    }