ApplicationContext应用上下文体系：
AbstractRefreshableApplicationContext主要是和容器的刷新与创建有关，调用refreshBeanFactory方法完成applicationContext.xml的解析操作，完成容器的初始化操作。
//类似于初始化容器，这里的容器就是DefaultListableBeanFactory @Override protected final void refreshBeanFactory() throws BeansException { //如果已经有容器，销毁容器中的bean，关闭容器 if (hasBeanFactory()) { destroyBeans(); closeBeanFactory(); } try { //创建IoC容器 DefaultListableBeanFactory beanFactory = createBeanFactory(); beanFactory.setSerializationId(getId()); //对IoC容器进行定制化，如设置启动参数，开启注解的自动装配等 customizeBeanFactory(beanFactory); //调用载入Bean定义的方法，主要这里又使用了一个委派模式，在当前类中只定义了抽象的loadBeanDefinitions方法，具体的实现调用子类容器 loadBeanDefinitions(beanFactory); synchronized (this.beanFactoryMonitor) { this.beanFactory = beanFactory; } } catch (IOException ex) { throw new ApplicationContextException("I/O error parsing bean definition source for " + getDisplayName(), ex); } }AbstractRefreshableApplicationContext也提供了一些容器操作的方法，完整的源码如下： /** * 主要是和容器刷新和创建相关 */ public abstract class AbstractRefreshableApplicationContext extends AbstractApplicationContext { private Boolean allowBeanDefinitionOverriding; private Boolean allowCircularReferences; private DefaultListableBeanFactory beanFactory; private final Object beanFactoryMonitor = new Object(); public AbstractRefreshableApplicationContext() { } public AbstractRefreshableApplicationContext(ApplicationContext parent) { super(parent); } public void setAllowBeanDefinitionOverriding(boolean allowBeanDefinitionOverriding) { this.allowBeanDefinitionOverriding = allowBeanDefinitionOverriding; } public void setAllowCircularReferences(boolean allowCircularReferences) { this.allowCircularReferences = allowCircularReferences; } //类似于初始化容器，这里的容器就是DefaultListableBeanFactory @Override protected final void refreshBeanFactory() throws BeansException { //如果已经有容器，销毁容器中的bean，关闭容器 if (hasBeanFactory()) { destroyBeans(); closeBeanFactory(); } try { //创建IoC容器 DefaultListableBeanFactory beanFactory = createBeanFactory(); beanFactory.setSerializationId(getId()); //对IoC容器进行定制化，如设置启动参数，开启注解的自动装配等 customizeBeanFactory(beanFactory); //调用载入Bean定义的方法，主要这里又使用了一个委派模式，在当前类中只定义了抽象的loadBeanDefinitions方法，具体的实现调用子类容器 loadBeanDefinitions(beanFactory); synchronized (this.beanFactoryMonitor) { this.beanFactory = beanFactory; } } catch (IOException ex) { throw new ApplicationContextException("I/O error parsing bean definition source for " + getDisplayName(), ex); } } //取消刷新 @Override protected void cancelRefresh(BeansException ex) { synchronized (this.beanFactoryMonitor) { if (this.beanFactory != null) this.beanFactory.setSerializationId(null); } super.cancelRefresh(ex); } //销毁工厂 @Override protected final void closeBeanFactory() { synchronized (this.beanFactoryMonitor) { this.beanFactory.setSerializationId(null); this.beanFactory = null; } } //判断Bean工厂是否还在 protected final boolean hasBeanFactory() { synchronized (this.beanFactoryMonitor) { return (this.beanFactory != null); } } //获取bean工厂 @Override public final ConfigurableListableBeanFactory getBeanFactory() { synchronized (this.beanFactoryMonitor) { if (this.beanFactory == null) { throw new IllegalStateException("BeanFactory not initialized or already closed - " + "call 'refresh' before accessing beans via the ApplicationContext"); } return this.beanFactory; } } @Override protected void assertBeanFactoryActive() { } //创建一个新的bean工厂 protected DefaultListableBeanFactory createBeanFactory() { return new DefaultListableBeanFactory(getInternalParentBeanFactory()); } protected void customizeBeanFactory(DefaultListableBeanFactory beanFactory) { if (this.allowBeanDefinitionOverriding != null) { beanFactory.setAllowBeanDefinitionOverriding(this.allowBeanDefinitionOverriding); } if (this.allowCircularReferences != null) { beanFactory.setAllowCircularReferences(this.allowCircularReferences); } } //读取applicationContext.xml中的配置 protected abstract void loadBeanDefinitions(DefaultListableBeanFactory beanFactory) throws BeansException, IOException; }