AbstractApplicationContext
public void refresh() throws BeansException, IllegalStateException {
synchronized (this.startupShutdownMonitor) {
// Prepare this context for refreshing.
prepareRefresh();//
// Tell the subclass to refresh the internal bean factory.
ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory(); //new出DefaultListableBeanFactory 加载BeanDefinitions
// Prepare the bean factory for use in this context.
prepareBeanFactory(beanFactory);
try {
// Allows post-processing of the bean factory in context subclasses.
postProcessBeanFactory(beanFactory);
// Invoke factory processors registered as beans in the context.
invokeBeanFactoryPostProcessors(beanFactory); // 执行所有的 BeanFactoryPostProcessor BeanDefinitionRegistryPostProcessor
//BeanFactoryPostProcessor 比如PropertyPlaceholderConfigurer替换${}
//BeanDefinitionRegistryPostProcessor 比如MapperScannerConfigurer注册动态代理生成的dao实例
// Register bean processors that intercept bean creation.
registerBeanPostProcessors(beanFactory);
//按顺序注册实现了PriorityOrdered Ordered 无序 的BeanPostProcessor
//挑选出MergedBeanDefinitionPostProcessor最后注册 注册时候会排重 加入到beanFactory的一个list中
// Initialize message source for this context.
initMessageSource();//初始化属性messageSource 若容器中没有使用默认的DelegatingMessageSource
// Initialize event multicaster for this context.
initApplicationEventMulticaster();//初始化属性applicationEventMulticaster 若容器中没有使用默认的SimpleApplicationEventMulticaster
// Initialize other special beans in specific context subclasses.
onRefresh();
// Check for listener beans and register them.
registerListeners();//applicationEventMulticaster加入容器中的ApplicationListener
// Instantiate all remaining (non-lazy-init) singletons.
finishBeanFactoryInitialization(beanFactory);//实例化所有的non-lazy-init
// Last step: publish corresponding event.
finishRefresh();
//实例化属性lifecycleProcessor 若容器没有使用DefaultLifecycleProcessor
//lifecycleProcessor.onRefresh()
//发布ContextRefreshedEvent
}
catch (BeansException ex) {
// Destroy already created singletons to avoid dangling resources.
destroyBeans();
// Reset 'active' flag.
cancelRefresh(ex);
// Propagate exception to caller.
throw ex;
}
}
}
//关闭容器
protected void doClose() {
boolean actuallyClose;
synchronized (this.activeMonitor) {
actuallyClose = this.active && !this.closed;
this.closed = true;
}
if (actuallyClose) {
if (logger.isInfoEnabled()) {
logger.info("Closing " + this);
}
LiveBeansView.unregisterApplicationContext(this);
try {
// Publish shutdown event.
publishEvent(new ContextClosedEvent(this));
}
catch (Throwable ex) {
logger.warn("Exception thrown from ApplicationListener handling ContextClosedEvent", ex);
}
// Stop all Lifecycle beans, to avoid delays during individual destruction.
try {
getLifecycleProcessor().onClose();
}
catch (Throwable ex) {
logger.warn("Exception thrown from LifecycleProcessor on context close", ex);
}
// Destroy all cached singletons in the context's BeanFactory.
destroyBeans();
// Close the state of this context itself.
closeBeanFactory();
// Let subclasses do some final clean-up if they wish...
onClose();
synchronized (this.activeMonitor) {
this.active = false;
}
}
}
AbstractAutowireCapableBeanFactory
@Override
protected Object createBean(final String beanName, final RootBeanDefinition mbd, final Object[] args)
throws BeanCreationException {
if (logger.isDebugEnabled()) {
logger.debug("Creating instance of bean '" + beanName + "'");
}
// Make sure bean class is actually resolved at this point.
resolveBeanClass(mbd, beanName);
// Prepare method overrides.
try {
mbd.prepareMethodOverrides();
}
catch (BeanDefinitionValidationException ex) {
throw new BeanDefinitionStoreException(mbd.getResourceDescription(),
beanName, "Validation of method overrides failed", ex);
}
try {
// Give BeanPostProcessors a chance to return a proxy instead of the target bean instance.
//使用InstantiationAwareBeanPostProcessor.postProcessBeforeInstantiation()得到bean 如果不为null
//接着执行所有的BeanPostProcessor.postProcessAfterInitialization()
Object bean = resolveBeforeInstantiation(beanName, mbd);
if (bean != null) {
return bean;
}
}
catch (Throwable ex) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName,
"BeanPostProcessor before instantiation of bean failed", ex);
}
Object beanInstance = doCreateBean(beanName, mbd, args);
if (logger.isDebugEnabled()) {
logger.debug("Finished creating instance of bean '" + beanName + "'");
}
return beanInstance;
}
/**
* Actually create the specified bean. Pre-creation processing has already happened
* at this point, e.g. checking {@code postProcessBeforeInstantiation} callbacks.
* <p>Differentiates between default bean instantiation, use of a
* factory method, and autowiring a constructor.
* @param beanName the name of the bean
* @param mbd the merged bean definition for the bean
* @param args arguments to use if creating a prototype using explicit arguments to a
* static factory method. This parameter must be {@code null} except in this case.
* @return a new instance of the bean
* @throws BeanCreationException if the bean could not be created
* @see #instantiateBean
* @see #instantiateUsingFactoryMethod
* @see #autowireConstructor
*/
protected Object doCreateBean(final String beanName, final RootBeanDefinition mbd, final Object[] args) {
// Instantiate the bean.
BeanWrapper instanceWrapper = null;
if (mbd.isSingleton()) {
instanceWrapper = this.factoryBeanInstanceCache.remove(beanName);
}
if (instanceWrapper == null) {
instanceWrapper = createBeanInstance(beanName, mbd, args);//生成一个实例
}
final Object bean = (instanceWrapper != null ? instanceWrapper.getWrappedInstance() : null);
Class<?> beanType = (instanceWrapper != null ? instanceWrapper.getWrappedClass() : null);
// Allow post-processors to modify the merged bean definition.
synchronized (mbd.postProcessingLock) {
if (!mbd.postProcessed) {
applyMergedBeanDefinitionPostProcessors(mbd, beanType, beanName);//执行MergedBeanDefinitionPostProcessor.postProcessMergedBeanDefinition()
mbd.postProcessed = true;
}
}
// Eagerly cache singletons to be able to resolve circular references
// even when triggered by lifecycle interfaces like BeanFactoryAware.
boolean earlySingletonExposure = (mbd.isSingleton() && this.allowCircularReferences &&
isSingletonCurrentlyInCreation(beanName));
if (earlySingletonExposure) {
if (logger.isDebugEnabled()) {
logger.debug("Eagerly caching bean '" + beanName +
"' to allow for resolving potential circular references");
}
addSingletonFactory(beanName, new ObjectFactory() {//单例类添加到SingletonBeanRegistry的map中缓存
public Object getObject() throws BeansException {
return getEarlyBeanReference(beanName, mbd, bean);
}
});
}
// Initialize the bean instance.
Object exposedObject = bean;
try {
populateBean(beanName, mbd, instanceWrapper);//初始化
//执行InstantiationAwareBeanPostProcessor.postProcessAfterInstantiation 有一个为false则返回
//设置mdb里面autowire的属性，从beanFactory里面取
//InstantiationAwareBeanPostProcessor.postProcessPropertyValues
//BeanWrapper中完成设置bean的属性
if (exposedObject != null) {
exposedObject = initializeBean(beanName, exposedObject, mbd);
//初始化后执行一些方法
//BeanNameAware.setBeanName
//BeanClassLoaderAware.setBeanClassLoader
//BeanFactoryAware.setBeanFactory
//BeanPostProcessor.postProcessBeforeInitialization
//InitializingBean.afterPropertiesSet
//initMethod
//BeanPostProcessor.postProcessAfterInitialization
//
}
}
catch (Throwable ex) {
if (ex instanceof BeanCreationException && beanName.equals(((BeanCreationException) ex).getBeanName())) {
throw (BeanCreationException) ex;
}
else {
throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Initialization of bean failed", ex);
}
}
if (earlySingletonExposure) {
Object earlySingletonReference = getSingleton(beanName, false);
if (earlySingletonReference != null) {
if (exposedObject == bean) {
exposedObject = earlySingletonReference;
}
else if (!this.allowRawInjectionDespiteWrapping && hasDependentBean(beanName)) {
String[] dependentBeans = getDependentBeans(beanName);
Set<String> actualDependentBeans = new LinkedHashSet<String>(dependentBeans.length);
for (String dependentBean : dependentBeans) {
if (!removeSingletonIfCreatedForTypeCheckOnly(dependentBean)) {
actualDependentBeans.add(dependentBean);
}
}
if (!actualDependentBeans.isEmpty()) {
throw new BeanCurrentlyInCreationException(beanName,
"Bean with name '" + beanName + "' has been injected into other beans [" +
StringUtils.collectionToCommaDelimitedString(actualDependentBeans) +
"] in its raw version as part of a circular reference, but has eventually been " +
"wrapped. This means that said other beans do not use the final version of the " +
"bean. This is often the result of over-eager type matching - consider using " +
"'getBeanNamesOfType' with the 'allowEagerInit' flag turned off, for example.");
}
}
}
}
// Register bean as disposable.
try {
registerDisposableBeanIfNecessary(beanName, bean, mbd);
//实现DisposableBean的bean加入到beanFactory的disposableBeans Map中
}
catch (BeanDefinitionValidationException ex) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Invalid destruction signature", ex);
}
return exposedObject;
}
//容器关闭时 销毁bean
DisposableBeanAdapter
public void destroy() {
if (this.beanPostProcessors != null && !this.beanPostProcessors.isEmpty()) {
for (DestructionAwareBeanPostProcessor processor : this.beanPostProcessors) {
processor.postProcessBeforeDestruction(this.bean, this.beanName);
}
}
if (this.invokeDisposableBean) {
if (logger.isDebugEnabled()) {
logger.debug("Invoking destroy() on bean with name '" + this.beanName + "'");
}
try {
if (System.getSecurityManager() != null) {
AccessController.doPrivileged(new PrivilegedExceptionAction<Object>() {
public Object run() throws Exception {
((DisposableBean) bean).destroy();
return null;
}
}, acc);
}
else {
((DisposableBean) bean).destroy();
}
}
catch (Throwable ex) {
String msg = "Invocation of destroy method failed on bean with name '" + this.beanName + "'";
if (logger.isDebugEnabled()) {
logger.warn(msg, ex);
}
else {
logger.warn(msg + ": " + ex);
}
}
}
if (this.destroyMethod != null) {
invokeCustomDestroyMethod(this.destroyMethod);
}
else if (this.destroyMethodName != null) {
Method methodToCall = determineDestroyMethod();
if (methodToCall != null) {
invokeCustomDestroyMethod(methodToCall);
}
}
}
大致过程
AbstractBeanFactory.getBean bean = InstantiationAwareBeanPostProcessor.postProcessBeforeInstantiation() if(bean == null) 实例化 MergedBeanDefinitionPostProcessor.postProcessMergedBeanDefinition() InstantiationAwareBeanPostProcessor.postProcessAfterInstantiation 初始化 BeanNameAware.setBeanName BeanClassLoaderAware.setBeanClassLoader BeanFactoryAware.setBeanFactory BeanPostProcessor.postProcessBeforeInitialization InitializingBean.afterPropertiesSet initMethod BeanPostProcessor.postProcessAfterInitialization -------------- AbstractApplicationContext.refresh BeanFactoryPostProcessor 扩展BeanFactoryPostProcessor BeanDefinitionRegistryPostProcessor registerBeanPostProcessors 注册 publishEvent(new ContextRefreshedEvent(this)); 扩展ApplicationListener -------------- AbstractApplicationContext.close publishEvent(new ContextClosedEvent(this)); DestructionAwareBeanPostProcessor.postProcessBeforeDestruction ((DisposableBean) bean).destroy(); destroyMethod