上一篇讲到了beanFactory的配置文件的解析和beanFactory的创建，都集中到了obtainFreshBeanFactory();这一句代码里了，本篇主要讲bean的创建过程

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(); // Prepare the bean factory for use in this context. prepareBeanFactory(beanFactory); try { //为容器的某些子类指定特殊的BeanPost事件处理器，默认是空 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(); // 实例化特殊的bean，空实现 onRefresh(); // Check for listener beans and register them. registerListeners(); // 初始化所有非懒加载的bean finishBeanFactoryInitialization(beanFactory); // Last step: publish corresponding event. finishRefresh(); } ... } }

首先，区分两个接口

public interface BeanFactoryPostProcessor {	void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException;}public interface BeanPostProcessor {	Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException;	Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException;}

前者是创建beanFactroy时候进行处理，后者是创建bean时进行处理

//由invokeBeanFactoryPostProcessors(beanFactory);进入，初始化BeanFactoryPostProcessors对容器进行自定义处理protected void invokeBeanFactoryPostProcessors(ConfigurableListableBeanFactory beanFactory) { PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(beanFactory, getBeanFactoryPostProcessors()); } //容器创建时beanFactoryPostProcessors为空 public static void invokeBeanFactoryPostProcessors( ConfigurableListableBeanFactory beanFactory, List
    
      beanFactoryPostProcessors) { // Invoke BeanDefinitionRegistryPostProcessors first, if any. Set
     
       processedBeans = new HashSet
      
       (); if (beanFactory instanceof BeanDefinitionRegistry) { BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory; List
       
         regularPostProcessors = new LinkedList
        
         (); List
         
           registryPostProcessors = new LinkedList
          
           (); ... //先初始化系统的BeanFactoryPostProcessor，最后初始化自己定义的 String[] postProcessorNames = beanFactory.getBeanNamesForType(BeanDefinitionRegistryPostProcessor.class, true, false); // First, invoke the BeanDefinitionRegistryPostProcessors that implement PriorityOrdered. List
           
             priorityOrderedPostProcessors = new ArrayList
            
             (); for (String ppName : postProcessorNames) { if (beanFactory.isTypeMatch(ppName, PriorityOrdered.class)) { priorityOrderedPostProcessors.add(beanFactory.getBean(ppName, BeanDefinitionRegistryPostProcessor.class)); processedBeans.add(ppName); } } sortPostProcessors(beanFactory, priorityOrderedPostProcessors); registryPostProcessors.addAll(priorityOrderedPostProcessors); invokeBeanDefinitionRegistryPostProcessors(priorityOrderedPostProcessors, registry); ... } else { // Invoke factory processors registered with the context instance. invokeBeanFactoryPostProcessors(beanFactoryPostProcessors, beanFactory); } // Do not initialize FactoryBeans here: We need to leave all regular beans // uninitialized to let the bean factory post-processors apply to them! String[] postProcessorNames = beanFactory.getBeanNamesForType(BeanFactoryPostProcessor.class, true, false); //此处获取到自定义的beanFactroyPostProcessor // Separate between BeanFactoryPostProcessors that implement PriorityOrdered, // Ordered, and the rest. List
             
               priorityOrderedPostProcessors = new ArrayList
              
               (); List
               
                 orderedPostProcessorNames = new ArrayList
                
                 (); List
                 
                   nonOrderedPostProcessorNames = new ArrayList
                  
                   (); for (String ppName : postProcessorNames) { if (processedBeans.contains(ppName)) { // skip - already processed in first phase above } else if (beanFactory.isTypeMatch(ppName, PriorityOrdered.class)) { priorityOrderedPostProcessors.add(beanFactory.getBean(ppName, BeanFactoryPostProcessor.class)); } else if (beanFactory.isTypeMatch(ppName, Ordered.class)) { orderedPostProcessorNames.add(ppName); } else { nonOrderedPostProcessorNames.add(ppName); } } // First, invoke the BeanFactoryPostProcessors that implement PriorityOrdered. sortPostProcessors(beanFactory, priorityOrderedPostProcessors); invokeBeanFactoryPostProcessors(priorityOrderedPostProcessors, beanFactory);//按顺序处理PriorityOrdered，Ordered和没加优先注解的 // Next, invoke the BeanFactoryPostProcessors that implement Ordered. List
                   
                     orderedPostProcessors = new ArrayList
                    
                     (); for (String postProcessorName : orderedPostProcessorNames) { orderedPostProcessors.add(beanFactory.getBean(postProcessorName, BeanFactoryPostProcessor.class)); } sortPostProcessors(beanFactory, orderedPostProcessors); invokeBeanFactoryPostProcessors(orderedPostProcessors, beanFactory); // Finally, invoke all other BeanFactoryPostProcessors. List
                     
                       nonOrderedPostProcessors = new ArrayList
                      
                       (); for (String postProcessorName : nonOrderedPostProcessorNames) { nonOrderedPostProcessors.add(beanFactory.getBean(postProcessorName, BeanFactoryPostProcessor.class)); //第一次初始化bfpp } invokeBeanFactoryPostProcessors(nonOrderedPostProcessors, beanFactory); // Clear cached merged bean definitions since the post-processors might have // modified the original metadata, e.g. replacing placeholders in values... beanFactory.clearMetadataCache(); } private static void invokeBeanFactoryPostProcessors( Collection
                        postProcessors, ConfigurableListableBeanFactory beanFactory) { for (BeanFactoryPostProcessor postProcessor : postProcessors) { postProcessor.postProcessBeanFactory(beanFactory);//此处对factory进行自定义处理 } }
                      
                     
                    
                   
                  
                 
                
               
              
             
            
           
          
         
        
       
      
     
    

接下来registerBeanPostProcessors(beanFactory);注册BeanPostProcessors

protected void registerBeanPostProcessors(ConfigurableListableBeanFactory beanFactory) { PostProcessorRegistrationDelegate.registerBeanPostProcessors(beanFactory, this); } public static void registerBeanPostProcessors( ConfigurableListableBeanFactory beanFactory, AbstractApplicationContext applicationContext) { String[] postProcessorNames = beanFactory.getBeanNamesForType(BeanPostProcessor.class, true, false); // Register BeanPostProcessorChecker that logs an info message when // a bean is created during BeanPostProcessor instantiation, i.e. when // a bean is not eligible for getting processed by all BeanPostProcessors. int beanProcessorTargetCount = beanFactory.getBeanPostProcessorCount() + 1 + postProcessorNames.length; beanFactory.addBeanPostProcessor(new BeanPostProcessorChecker(beanFactory, beanProcessorTargetCount)); // Separate between BeanPostProcessors that implement PriorityOrdered, // Ordered, and the rest. List
    
      priorityOrderedPostProcessors = new ArrayList
     
      (); List
      
        internalPostProcessors = new ArrayList
       
        (); List
        
          orderedPostProcessorNames = new ArrayList
         
          (); List
          
            nonOrderedPostProcessorNames = new ArrayList
           
            (); for (String ppName : postProcessorNames) { if (beanFactory.isTypeMatch(ppName, PriorityOrdered.class)) { BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class); priorityOrderedPostProcessors.add(pp); if (pp instanceof MergedBeanDefinitionPostProcessor) { internalPostProcessors.add(pp); } } else if (beanFactory.isTypeMatch(ppName, Ordered.class)) { orderedPostProcessorNames.add(ppName); } else { nonOrderedPostProcessorNames.add(ppName); } } // First, register the BeanPostProcessors that implement PriorityOrdered. sortPostProcessors(beanFactory, priorityOrderedPostProcessors); registerBeanPostProcessors(beanFactory, priorityOrderedPostProcessors); // Next, register the BeanPostProcessors that implement Ordered. List
            
              orderedPostProcessors = new ArrayList
             
              (); for (String ppName : orderedPostProcessorNames) { BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class); orderedPostProcessors.add(pp); if (pp instanceof MergedBeanDefinitionPostProcessor) { internalPostProcessors.add(pp); } } sortPostProcessors(beanFactory, orderedPostProcessors); registerBeanPostProcessors(beanFactory, orderedPostProcessors); // Now, register all regular BeanPostProcessors. List
              
                nonOrderedPostProcessors = new ArrayList
               
                (); for (String ppName : nonOrderedPostProcessorNames) { BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class); //跟bfpp如出一辙 nonOrderedPostProcessors.add(pp); if (pp instanceof MergedBeanDefinitionPostProcessor) { internalPostProcessors.add(pp); } } registerBeanPostProcessors(beanFactory, nonOrderedPostProcessors); // Finally, re-register all internal BeanPostProcessors. sortPostProcessors(beanFactory, internalPostProcessors); registerBeanPostProcessors(beanFactory, internalPostProcessors); beanFactory.addBeanPostProcessor(new ApplicationListenerDetector(applicationContext)); } private static void registerBeanPostProcessors( ConfigurableListableBeanFactory beanFactory, List
                
                  postProcessors) { for (BeanPostProcessor postProcessor : postProcessors) { beanFactory.addBeanPostProcessor(postProcessor); } } public void addBeanPostProcessor(BeanPostProcessor beanPostProcessor) { Assert.notNull(beanPostProcessor, "BeanPostProcessor must not be null"); this.beanPostProcessors.remove(beanPostProcessor); //先删后加，这样就不会重复添加了 this.beanPostProcessors.add(beanPostProcessor); ... }
                
               
              
             
            
           
          
         
        
       
      
     
    

执行finishBeanFactoryInitialization(beanFactory);初始化所有非懒加载的bean

protected void finishBeanFactoryInitialization(ConfigurableListableBeanFactory beanFactory) ... // Instantiate all remaining (non-lazy-init) singletons. beanFactory.preInstantiateSingletons(); } public void preInstantiateSingletons() throws BeansException { ... List
    
      beanNames = new ArrayList
     
      (this.beanDefinitionNames); // Trigger initialization of all non-lazy singleton beans... for (String beanName : beanNames) { RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName); //根据指定Bean名称获取其父级的Bean定义，主要解决Bean继承时子类合并父类公共属性问题 if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) { if (isFactoryBean(beanName)) { final FactoryBean
       factory = (FactoryBean
      ) getBean(FACTORY_BEAN_PREFIX + beanName); //factoryBean初始化 ... } else { getBean(beanName); //普通bean初始化 } } } // 在所有bean加载后，调用SmartInitializingSingleton的方法 for (String beanName : beanNames) { Object singletonInstance = getSingleton(beanName); if (singletonInstance instanceof SmartInitializingSingleton) { final SmartInitializingSingleton smartSingleton = (SmartInitializingSingleton) singletonInstance; ... smartSingleton.afterSingletonsInstantiated(); } } }
     
    

上图是创建bean的过程

下面分析关键代码beanFactory.getBean()方法

//AbstractBeanFactorypublic Object getBean(String name) throws BeansException { return doGetBean(name, null, null, false); } protected 
    
      T doGetBean( final String name, final Class
     
       requiredType, final Object[] args, boolean typeCheckOnly) throws BeansException { final String beanName = transformedBeanName(name);//会把别名，&facBeanName转换为规范的Bean名称 Object bean; Object sharedInstance = getSingleton(beanName); //先在单例map中找 if (sharedInstance != null && args == null) { ... bean = getObjectForBeanInstance(sharedInstance, name, beanName, null); } else { // Fail if we're already creating this bean instance: // We're assumably within a circular reference. if (isPrototypeCurrentlyInCreation(beanName)) { throw new BeanCurrentlyInCreationException(beanName); } BeanFactory parentBeanFactory = getParentBeanFactory(); if (parentBeanFactory != null && !containsBeanDefinition(beanName)) { //本工厂找不到上父工厂找 String nameToLookup = originalBeanName(name); if (args != null) { return (T) parentBeanFactory.getBean(nameToLookup, args); } else { // No args -> delegate to standard getBean method. return parentBeanFactory.getBean(nameToLookup, requiredType); } } if (!typeCheckOnly) { markBeanAsCreated(beanName); } try { final RootBeanDefinition mbd = getMergedLocalBeanDefinition(beanName); checkMergedBeanDefinition(mbd, beanName, args); //是abstract的抛异常 // Guarantee initialization of beans that the current bean depends on. String[] dependsOn = mbd.getDependsOn(); if (dependsOn != null) { for (String dependsOnBean : dependsOn) { if (isDependent(beanName, dependsOnBean)) { //循环依赖抛异常 throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Circular depends-on relationship between '" + beanName + "' and '" + dependsOnBean + "'"); } registerDependentBean(dependsOnBean, beanName); getBean(dependsOnBean);//有depends-on的bean优先创建 } } // Create bean instance. if (mbd.isSingleton()) { sharedInstance = getSingleton(beanName, new ObjectFactory
      
     
    

在单例池中取出，获取给定Bean的实例对象，主要是完成FactoryBean的相关处理

protected Object getObjectForBeanInstance(			Object beanInstance, String name, String beanName, RootBeanDefinition mbd) {		// Don't let calling code try to dereference the factory if the bean isn't a factory. if (BeanFactoryUtils.isFactoryDereference(name) && !(beanInstance instanceof FactoryBean)) { throw new BeanIsNotAFactoryException(transformedBeanName(name), beanInstance.getClass()); } //若果是FactroyBean，但是取的名字没加&引用代表取工厂bean，那就代表要取工厂创建的bean了，如果不是FactroyBean，就直接返回了 if (!(beanInstance instanceof FactoryBean) || BeanFactoryUtils.isFactoryDereference(name)) { return beanInstance; } Object object = null; if (mbd == null) { object = getCachedObjectForFactoryBean(beanName); } if (object == null) { // Return bean instance from factory. FactoryBean
     factory = (FactoryBean
    ) beanInstance; // Caches object obtained from FactoryBean if it is a singleton. if (mbd == null && containsBeanDefinition(beanName)) { mbd = getMergedLocalBeanDefinition(beanName); } boolean synthetic = (mbd != null && mbd.isSynthetic()); object = getObjectFromFactoryBean(factory, beanName, !synthetic); } return object; }

在AbstractBeanFactory里存有Map<String, RootBeanDefinition> mergedBeanDefinitions，注意同DefaultListableBeanFactory里的Map<String, BeanDefinition> beanDefinitionMap区分

RootBeanDefinition是在运行中由GenericBeanDefinition动态合成的，配置文件中的bean可能有父子关系，因而可能有合并过程。

protected void markBeanAsCreated(String beanName) { if (!this.alreadyCreated.contains(beanName)) { this.alreadyCreated.add(beanName); clearMergedBeanDefinition(beanName); } } protected void clearMergedBeanDefinition(String beanName) { this.mergedBeanDefinitions.remove(beanName); } protected RootBeanDefinition getMergedLocalBeanDefinition(String beanName) throws BeansException { // Quick check on the concurrent map first, with minimal locking. RootBeanDefinition mbd = this.mergedBeanDefinitions.get(beanName); if (mbd != null) { return mbd; } return getMergedBeanDefinition(beanName, getBeanDefinition(beanName)); } //在子类DefaultListableBeanFactory实现 public BeanDefinition getBeanDefinition(String beanName) throws NoSuchBeanDefinitionException { BeanDefinition bd = this.beanDefinitionMap.get(beanName); if (bd == null) { ... throw new NoSuchBeanDefinitionException(beanName); } return bd; } protected RootBeanDefinition getMergedBeanDefinition(String beanName, BeanDefinition bd) throws BeanDefinitionStoreException { return getMergedBeanDefinition(beanName, bd, null); } protected RootBeanDefinition getMergedBeanDefinition( String beanName, BeanDefinition bd, BeanDefinition containingBd) throws BeanDefinitionStoreException { synchronized (this.mergedBeanDefinitions) { RootBeanDefinition mbd = null; // Check with full lock now in order to enforce the same merged instance. if (containingBd == null) { mbd = this.mergedBeanDefinitions.get(beanName); } if (mbd == null) { if (bd.getParentName() == null) { // Use copy of given root bean definition. if (bd instanceof RootBeanDefinition) { mbd = ((RootBeanDefinition) bd).cloneBeanDefinition(); } else { mbd = new RootBeanDefinition(bd); } } else { ... mbd = new RootBeanDefinition(pbd); mbd.overrideFrom(bd); } // Set default singleton scope, if not configured before. if (!StringUtils.hasLength(mbd.getScope())) { mbd.setScope(RootBeanDefinition.SCOPE_SINGLETON); } // A bean contained in a non-singleton bean cannot be a singleton itself. // Let's correct this on the fly here, since this might be the result of // parent-child merging for the outer bean, in which case the original inner bean // definition will not have inherited the merged outer bean's singleton status. if (containingBd != null && !containingBd.isSingleton() && mbd.isSingleton()) { mbd.setScope(containingBd.getScope()); } // Only cache the merged bean definition if we're already about to create an // instance of the bean, or at least have already created an instance before. if (containingBd == null && isCacheBeanMetadata()) { this.mergedBeanDefinitions.put(beanName, mbd); } } return mbd; } }

先分析下单例

if (mbd.isSingleton()) {	sharedInstance = getSingleton(beanName, new ObjectFactory

进入DefaultSingletonBeanRegistry，Map<String, Object> singletonObjects存于此处

public Object getSingleton(String beanName, ObjectFactory
     singletonFactory) {		Assert.notNull(beanName, "'beanName' must not be null"); synchronized (this.singletonObjects) { Object singletonObject = this.singletonObjects.get(beanName); if (singletonObject == null) { ... singletonObject = singletonFactory.getObject(); //回调匿名内部类的createBean方法 newSingleton = true; ... if (newSingleton) { addSingleton(beanName, singletonObject); } } return (singletonObject != NULL_OBJECT ? singletonObject : null); } }

进入AbstractAutowireCapableBeanFactory来创建bean

protected Object createBean(String beanName, RootBeanDefinition mbd, Object[] args) throws BeanCreationException { if (logger.isDebugEnabled()) { logger.debug("Creating instance of bean '" + beanName + "'"); } RootBeanDefinition mbdToUse = mbd; ... try { // Give BeanPostProcessors a chance to return a proxy instead of the target bean instance. Object bean = resolveBeforeInstantiation(beanName, mbdToUse); if (bean != null) { return bean; //bbp有特殊处理的话就先返回 } } catch (Throwable ex) { throw new BeanCreationException(mbdToUse.getResourceDescription(), beanName, "BeanPostProcessor before instantiation of bean failed", ex); } Object beanInstance = doCreateBean(beanName, mbdToUse, args); //真正创建bean if (logger.isDebugEnabled()) { logger.debug("Finished creating instance of bean '" + beanName + "'"); } return beanInstance; } protected Object resolveBeforeInstantiation(String beanName, RootBeanDefinition mbd) { Object bean = null; if (!Boolean.FALSE.equals(mbd.beforeInstantiationResolved)) { // Make sure bean class is actually resolved at this point. if (!mbd.isSynthetic() && hasInstantiationAwareBeanPostProcessors()) { Class
     targetType = determineTargetType(beanName, mbd); if (targetType != null) { bean = applyBeanPostProcessorsBeforeInstantiation(targetType, beanName); if (bean != null) { bean = applyBeanPostProcessorsAfterInitialization(bean, beanName); //普通bpp } } } mbd.beforeInstantiationResolved = (bean != null); } return bean; } //这里的BeanPostProcessor必须要实现这个接口 public interface InstantiationAwareBeanPostProcessor extends BeanPostProcessor { Object postProcessBeforeInstantiation(Class
     beanClass, String beanName) throws BeansException; .. } 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); //开始创建bean } 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); //触发MergedBeanDefinitionPostProcessor 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

接下来分析下bean的属性注入

protected void populateBean(String beanName, RootBeanDefinition mbd, BeanWrapper bw) { PropertyValues pvs = mbd.getPropertyValues(); ... if (mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_BY_NAME || mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_BY_TYPE) { //通过名字或属性自动注入 MutablePropertyValues newPvs = new MutablePropertyValues(pvs); // Add property values based on autowire by name if applicable. if (mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_BY_NAME) { autowireByName(beanName, mbd, bw, newPvs); } // Add property values based on autowire by type if applicable. if (mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_BY_TYPE) { autowireByType(beanName, mbd, bw, newPvs); } pvs = newPvs; } ... applyPropertyValues(beanName, mbd, bw, pvs); } protected void applyPropertyValues(String beanName, BeanDefinition mbd, BeanWrapper bw, PropertyValues pvs) { if (pvs == null || pvs.isEmpty()) { return; } MutablePropertyValues mpvs = null; List
    
      original; ... if (pvs instanceof MutablePropertyValues) { mpvs = (MutablePropertyValues) pvs; if (mpvs.isConverted()) { // Shortcut: use the pre-converted values as-is. try { bw.setPropertyValues(mpvs); return; } catch (BeansException ex) { throw new BeanCreationException( mbd.getResourceDescription(), beanName, "Error setting property values", ex); } } original = mpvs.getPropertyValueList(); } else { original = Arrays.asList(pvs.getPropertyValues()); } TypeConverter converter = getCustomTypeConverter(); if (converter == null) { converter = bw; } BeanDefinitionValueResolver valueResolver = new BeanDefinitionValueResolver(this, beanName, mbd, converter); // Create a deep copy, resolving any references for values. List
     
       deepCopy = new ArrayList
      
       (original.size()); boolean resolveNecessary = false; for (PropertyValue pv : original) { if (pv.isConverted()) { deepCopy.add(pv); } else { String propertyName = pv.getName(); Object originalValue = pv.getValue(); //看是哪种pv了，解析成相应的原值 Object resolvedValue = valueResolver.resolveValueIfNecessary(pv, originalValue); Object convertedValue = resolvedValue; //如果为runtimeRef，就会创建引用的bean了 boolean convertible = bw.isWritableProperty(propertyName) && !PropertyAccessorUtils.isNestedOrIndexedProperty(propertyName); if (convertible) { convertedValue = convertForProperty(resolvedValue, propertyName, bw, converter); } ... deepCopy.add(new PropertyValue(pv, convertedValue)); ... } } if (mpvs != null && !resolveNecessary) { mpvs.setConverted(); } //在此注入值 try { bw.setPropertyValues(new MutablePropertyValues(deepCopy)); } catch (BeansException ex) { throw new BeanCreationException( mbd.getResourceDescription(), beanName, "Error setting property values", ex); } } public Object resolveValueIfNecessary(Object argName, Object value) { if (value instanceof RuntimeBeanReference) { RuntimeBeanReference ref = (RuntimeBeanReference) value; return resolveReference(argName, ref); } ... } private Object resolveReference(Object argName, RuntimeBeanReference ref) { ... Object bean = this.beanFactory.getBean(refName); this.beanFactory.registerDependentBean(refName, this.beanName); return bean; }
      
     
    

继续执行初始化

protected Object initializeBean(final String beanName, final Object bean, RootBeanDefinition mbd) { ... invokeAwareMethods(beanName, bean); //看有无实现beanAware相关接口，有则进行注入 Object wrappedBean = bean; if (mbd == null || !mbd.isSynthetic()) { wrappedBean = applyBeanPostProcessorsBeforeInitialization(wrappedBean, beanName); //bbp前置处理 } try { invokeInitMethods(beanName, wrappedBean, mbd); } catch (Throwable ex) { throw new BeanCreationException( (mbd != null ? mbd.getResourceDescription() : null), beanName, "Invocation of init method failed", ex); } if (mbd == null || !mbd.isSynthetic()) { wrappedBean = applyBeanPostProcessorsAfterInitialization(wrappedBean, beanName); //bbp后置处理 } return wrappedBean; } public Object applyBeanPostProcessorsBeforeInitialization(Object existingBean, String beanName) throws BeansException { Object result = existingBean; for (BeanPostProcessor beanProcessor : getBeanPostProcessors()) { result = beanProcessor.postProcessBeforeInitialization(result, beanName); if (result == null) { return result; } } return result; } protected void invokeInitMethods(String beanName, final Object bean, RootBeanDefinition mbd) throws Throwable { boolean isInitializingBean = (bean instanceof InitializingBean); if (isInitializingBean && (mbd == null || !mbd.isExternallyManagedInitMethod("afterPropertiesSet"))) { ... ((InitializingBean) bean).afterPropertiesSet(); } if (mbd != null) { String initMethodName = mbd.getInitMethodName(); if (initMethodName != null && !(isInitializingBean && "afterPropertiesSet".equals(initMethodName)) && !mbd.isExternallyManagedInitMethod(initMethodName)) { invokeCustomInitMethod(beanName, bean, mbd); //调用初始方法 } } }