finishBeanFactoryInitialization
实例化BeanFactory
源码
protected void finishBeanFactoryInitialization(ConfigurableListableBeanFactory beanFactory) {
// Initialize conversion service for this context.
//设置上线问类型转换器
if (beanFactory.containsBean(CONVERSION_SERVICE_BEAN_NAME) &&
beanFactory.isTypeMatch(CONVERSION_SERVICE_BEAN_NAME, ConversionService.class)) {
beanFactory.setConversionService(
beanFactory.getBean(CONVERSION_SERVICE_BEAN_NAME, ConversionService.class));
}
// Initialize LoadTimeWeaverAware beans early to allow for registering their transformers early.
String[] weaverAwareNames = beanFactory.getBeanNamesForType(LoadTimeWeaverAware.class, false, false);
for (String weaverAwareName : weaverAwareNames) {
getBean(weaverAwareName);
}
// Stop using the temporary ClassLoader for type matching.
beanFactory.setTempClassLoader(null);
// Allow for caching all bean definition metadata, not expecting further changes.
//冻结所有的Bean定义 ， 至此注册的Bean定义将不被修改或任何进一步的处理
beanFactory.freezeConfiguration();
// Instantiate all remaining (non-lazy-init) singletons.
//准备实例化bean
beanFactory.preInstantiateSingletons();
}
preInstantiateSingletons方法：
源码：
public void preInstantiateSingletons() throws BeansException {
if (this.logger.isDebugEnabled()) {
this.logger.debug("Pre-instantiating singletons in " + this);
}
List<String> beanNames = new ArrayList(this.beanDefinitionNames);
Iterator var2 = beanNames.iterator();
//对延迟加载的非单例的进行实例化
while(true) {
while(true) {
String beanName;
RootBeanDefinition bd;
do {
do {
do {
if (!var2.hasNext()) {
var2 = beanNames.iterator();
while(var2.hasNext()) {
beanName = (String)var2.next();
//加载单例
Object singletonInstance = this.getSingleton(beanName);
if (singletonInstance instanceof SmartInitializingSingleton) {
final SmartInitializingSingleton smartSingleton = (SmartInitializingSingleton)singletonInstance;
if (System.getSecurityManager() != null) {
AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
smartSingleton.afterSingletonsInstantiated();
return null;
}
}, this.getAccessControlContext());
} else {
smartSingleton.afterSingletonsInstantiated();
}
}
}
return;
}
beanName = (String)var2.next();
bd = this.getMergedLocalBeanDefinition(beanName);
} while(bd.isAbstract());
} while(!bd.isSingleton());
} while(bd.isLazyInit());
//非懒加载的bean进行实例化
if (this.isFactoryBean(beanName)) {
final FactoryBean<?> factory = (FactoryBean)this.getBean("&" + beanName);
boolean isEagerInit;
if (System.getSecurityManager() != null && factory instanceof SmartFactoryBean) {
isEagerInit = (Boolean)AccessController.doPrivileged(new PrivilegedAction<Boolean>() {
public Boolean run() {
return ((SmartFactoryBean)factory).isEagerInit();
}
}, this.getAccessControlContext());
} else {
isEagerInit = factory instanceof SmartFactoryBean && ((SmartFactoryBean)factory).isEagerInit();
}
if (isEagerInit) {
this.getBean(beanName);
}
} else {
this.getBean(beanName);
}
}
}
}
getSingleton：
获取单例，使用三级缓存解决循环依赖
protected Object getSingleton(String beanName, boolean allowEarlyReference) {
////在已经注册了的单例map集合（singletonObjects）中获取特定beanName的bean
Object singletonObject = this.singletonObjects.get(beanName);
//若获取不到，并且对象正在创建中
if (singletonObject == null && this.isSingletonCurrentlyInCreation(beanName)) {
synchronized(this.singletonObjects) {
//从二级缓存earlySingletonObjects中获取
singletonObject = this.earlySingletonObjects.get(beanName);
//如果还是获取不到且允许singletonFactories通过getObject()获取，就从三级缓存singletonFactory.getObject()(三级缓存)获取
if (singletonObject == null && allowEarlyReference) {
ObjectFactory<?> singletonFactory = (ObjectFactory)this.singletonFactories.get(beanName);
if (singletonFactory != null) {
singletonObject = singletonFactory.getObject();
this.earlySingletonObjects.put(beanName, singletonObject);
this.singletonFactories.remove(beanName);
}
}
}
}
return singletonObject != NULL_OBJECT ? singletonObject : null;
}
getBean():
public Object getBean(String name) throws BeansException {
return this.doGetBean(name, (Class)null, (Object[])null, false);
}
doGetBean:
protected <T> T doGetBean(String name, Class<T> requiredType, final Object[] args, boolean typeCheckOnly) throws BeansException {
//获取beanName
final String beanName = this.transformedBeanName(name);
//先从缓存中获取
//1
Object sharedInstance = this.getSingleton(beanName);
Object bean;
//缓存命中
if (sharedInstance != null && args == null) {
if (this.logger.isDebugEnabled()) {
if (this.isSingletonCurrentlyInCreation(beanName)) {
this.logger.debug("Returning eagerly cached instance of singleton bean '" + beanName + "' that is not fully initialized yet - a consequence of a circular reference");
} else {
this.logger.debug("Returning cached instance of singleton bean '" + beanName + "'");
}
}
//如果sharedInstance是普通的单例bean，下面的方法会直接返回
//如果是是FactoryBean类型的，则需调用getObject工厂方法获取真正的bean实例
bean = this.getObjectForBeanInstance(sharedInstance, name, beanName, (RootBeanDefinition)null);
} else {
//Spring只能解决单例对象的setter注入的循环依赖,不能解决构造器注入，也不能解决多实例的循环依赖
//2
if (this.isPrototypeCurrentlyInCreation(beanName)) {
throw new BeanCurrentlyInCreationException(beanName);
}
BeanFactory parentBeanFactory = this.getParentBeanFactory();
//若存在父工厂,切当前的bean工厂不存在当前的bean定义,那么bean定义是存在于父beanFactory中
if (parentBeanFactory != null && !this.containsBeanDefinition(beanName)) {
String nameToLookup = this.originalBeanName(name);
if (args != null) {
return parentBeanFactory.getBean(nameToLookup, args);
}
return parentBeanFactory.getBean(nameToLookup, requiredType);
}
/**
* 方法参数typeCheckOnly ，是用来判断调用getBean(...) 方法时，表示是否为仅仅进行类型检查获取Bean对象
* 如果不是仅仅做类型检查，而是创建Bean对象，则需要调用markBeanAsCreated(String beanName) 方法，进行记录
*/
if (!typeCheckOnly) {
this.markBeanAsCreated(beanName);
}
try {
//从容器中获取beanName相应的GenericBeanDefinition对象，并将其转换为RootBeanDefinition对象
//3
final RootBeanDefinition mbd = this.getMergedLocalBeanDefinition(beanName);
//4
this.checkMergedBeanDefinition(mbd, beanName, args);
//处理dependsOn的依赖(这个不是我们所谓的循环依赖 而是bean创建前后的依赖，@DependsOn注解)
//依赖bean的名称
String[] dependsOn = mbd.getDependsOn();
String[] var11;
if (dependsOn != null) {
var11 = dependsOn;
int var12 = dependsOn.length;
for(int var13 = 0; var13 < var12; ++var13) {
String dependsOnBean = var11[var13];
if (this.isDependent(beanName, dependsOnBean)) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Circular depends-on relationship between '" + beanName + "' and '" + dependsOnBean + "'");
}
//保存的是依赖beanName之间的映射关系：依赖beanName -> beanName的集合
this.registerDependentBean(dependsOnBean, beanName);
this.getBean(dependsOnBean);
}
}
//是单例则创建单例Bean
5
if (mbd.isSingleton()) {
sharedInstance = this.getSingleton(beanName, new ObjectFactory<Object>() {
public Object getObject() throws BeansException {
try {
return AbstractBeanFactory.this.createBean(beanName, mbd, args);
} catch (BeansException var2) {
AbstractBeanFactory.this.destroySingleton(beanName);
throw var2;
}
}
});
bean = this.getObjectForBeanInstance(sharedInstance, name, beanName, mbd);
} else if (mbd.isPrototype()) {
var11 = null;
Object prototypeInstance;
try {
this.beforePrototypeCreation(beanName);
prototypeInstance = this.createBean(beanName, mbd, args);
} finally {
this.afterPrototypeCreation(beanName);
}
bean = this.getObjectForBeanInstance(prototypeInstance, name, beanName, mbd);
} else {
String scopeName = mbd.getScope();
Scope scope = (Scope)this.scopes.get(scopeName);
if (scope == null) {
throw new IllegalStateException("No Scope registered for scope name '" + scopeName + "'");
}
try {
Object scopedInstance = scope.get(beanName, new ObjectFactory<Object>() {
public Object getObject() throws BeansException {
AbstractBeanFactory.this.beforePrototypeCreation(beanName);
Object var1;
try {
var1 = AbstractBeanFactory.this.createBean(beanName, mbd, args);
} finally {
AbstractBeanFactory.this.afterPrototypeCreation(beanName);
}
return var1;
}
});
bean = this.getObjectForBeanInstance(scopedInstance, name, beanName, mbd);
} catch (IllegalStateException var21) {
throw new BeanCreationException(beanName, "Scope '" + scopeName + "' is not active for the current thread; consider " + "defining a scoped proxy for this bean if you intend to refer to it from a singleton", var21);
}
}
} catch (BeansException var23) {
this.cleanupAfterBeanCreationFailure(beanName);
throw var23;
}
}
if (requiredType != null && bean != null && !requiredType.isAssignableFrom(bean.getClass())) {
try {
return this.getTypeConverter().convertIfNecessary(bean, requiredType);
} catch (TypeMismatchException var22) {
if (this.logger.isDebugEnabled()) {
this.logger.debug("Failed to convert bean '" + name + "' to required type [" + ClassUtils.getQualifiedName(requiredType) + "]", var22);
}
throw new BeanNotOfRequiredTypeException(name, requiredType, bean.getClass());
}
} else {
return bean;
}
}
一：先尝试去缓存中获取对象
二：spring只能解决setter注入的的循环依赖，不能解决构造器注入产生的循环依赖，所以会抛出bean正在创建的异常，接着判断是否有父工厂，有就调用父工厂的getBean，如果不是仅仅做类型检查，而是创建Bean对象，则需要调用markBeanAsCreated方法进行标识
三：合并bean定义信息
getMergedLocalBeanDefinition：
protected RootBeanDefinition getMergedLocalBeanDefinition(String beanName) throws BeansException {
//如果能直接获取到bean定义，直接返回
RootBeanDefinition mbd = (RootBeanDefinition)this.mergedBeanDefinitions.get(beanName);
//否则获取 RootBeanDefinition 对象
return mbd != null ? mbd : this.getMergedBeanDefinition(beanName, this.getBeanDefinition(beanName));
}
getMergedBeanDefinition：
protected RootBeanDefinition getMergedBeanDefinition(String beanName, BeanDefinition bd, BeanDefinition containingBd) throws BeanDefinitionStoreException {
//整段的意思就是递归调用getMergedBeanDefinition合并父类BeanDefinition，并转换成RootBeanDefinition
synchronized(this.mergedBeanDefinitions) {
RootBeanDefinition mbd = null;
if (containingBd == null) {
mbd = (RootBeanDefinition)this.mergedBeanDefinitions.get(beanName);
}
if (mbd == null) {
if (bd.getParentName() == null) {
if (bd instanceof RootBeanDefinition) {
mbd = ((RootBeanDefinition)bd).cloneBeanDefinition();
} else {
mbd = new RootBeanDefinition(bd);
}
} else {
BeanDefinition pbd;
try {
String parentBeanName = this.transformedBeanName(bd.getParentName());
if (!beanName.equals(parentBeanName)) {
pbd = this.getMergedBeanDefinition(parentBeanName);
} else {
if (!(this.getParentBeanFactory() instanceof ConfigurableBeanFactory)) {
throw new NoSuchBeanDefinitionException(bd.getParentName(), "Parent name '" + bd.getParentName() + "' is equal to bean name '" + beanName + "': cannot be resolved without an AbstractBeanFactory parent");
}
pbd = ((ConfigurableBeanFactory)this.getParentBeanFactory()).getMergedBeanDefinition(parentBeanName);
}
} catch (NoSuchBeanDefinitionException var9) {
throw new BeanDefinitionStoreException(bd.getResourceDescription(), beanName, "Could not resolve parent bean definition '" + bd.getParentName() + "'", var9);
}
mbd = new RootBeanDefinition(pbd);
mbd.overrideFrom(bd);
}
//无scope定义，默认为单例的
if (!StringUtils.hasLength(mbd.getScope())) {
mbd.setScope("singleton");
}
if (containingBd != null && !containingBd.isSingleton() && mbd.isSingleton()) {
mbd.setScope(containingBd.getScope());
}
if (containingBd == null && this.isCacheBeanMetadata()) {
this.mergedBeanDefinitions.put(beanName, mbd);
}
}
return mbd;
}
}
四：然后检查当前创建的bean定义是不是抽象的bean定义
checkMergedBeanDefinition
protected void checkMergedBeanDefinition(RootBeanDefinition mbd, String beanName, Object[] args) throws BeanDefinitionStoreException {
//抽象的bean不能实例化
if (mbd.isAbstract()) {
throw new BeanIsAbstractException(beanName);
}
}
5处理Dependson循环依赖（@DependsOn）
isDependent
private boolean isDependent(String beanName, String dependentBeanName, Set<String> alreadySeen) {
String canonicalName = this.canonicalName(beanName);
if (alreadySeen != null && ((Set)alreadySeen).contains(beanName)) {
return false;
} else {
Set<String> dependentBeans = (Set)this.dependentBeanMap.get(canonicalName);
if (dependentBeans == null) {
return false;
//这里是循环依赖的判断方法，如果依赖已经注册过，则证明产生循环依赖，抛出异常
} else if (dependentBeans.contains(dependentBeanName)) {
return true;
} else {
Iterator var6 = dependentBeans.iterator();
String transitiveDependency;
do {
if (!var6.hasNext()) {
return false;
}
transitiveDependency = (String)var6.next();
if (alreadySeen == null) {
alreadySeen = new HashSet();
}
((Set)alreadySeen).add(beanName);
} while(!this.isDependent(transitiveDependency, dependentBeanName, (Set)alreadySeen));
return true;
}
}
}
registerDependentBean
public void registerDependentBean(String beanName, String dependentBeanName) {
//该方法作用是将依赖bean和当前bean写入到一个map里（dependenciesForBeanMap）
String canonicalName = this.canonicalName(beanName);
Set<String> dependentBeans = (Set)this.dependentBeanMap.get(canonicalName);
if (dependentBeans == null || !dependentBeans.contains(dependentBeanName)) {
synchronized(this.dependentBeanMap) {
Set<String> dependentBeans = (Set)this.dependentBeanMap.get(canonicalName);
if (dependentBeans == null) {
dependentBeans = new LinkedHashSet(8);
this.dependentBeanMap.put(canonicalName, dependentBeans);
}
((Set)dependentBeans).add(dependentBeanName);
}
synchronized(this.dependenciesForBeanMap) {
Set<String> dependenciesForBean = (Set)this.dependenciesForBeanMap.get(dependentBeanName);
if (dependenciesForBean == null) {
dependenciesForBean = new LinkedHashSet(8);
this.dependenciesForBeanMap.put(dependentBeanName, dependenciesForBean);
}
((Set)dependenciesForBean).add(canonicalName);
}
}
}
然后不断实例化依赖bean（递归实现），完成了依赖bean的实例化
五：处理单实例bean
public Object getSingleton(String beanName, ObjectFactory<?> singletonFactory) {
Assert.notNull(beanName, "'beanName' must not be null");
synchronized(this.singletonObjects) {
//检查bean是否再缓存池中
Object singletonObject = this.singletonObjects.get(beanName);
if (singletonObject == null) {
if (this.singletonsCurrentlyInDestruction) {
//别在destroy方法里请求bean（笑）
throw new BeanCreationNotAllowedException(beanName, "Singleton bean creation not allowed while the singletons of this factory are in destruction (Do not request a bean from a BeanFactory in a destroy method implementation!)");
}
if (this.logger.isDebugEnabled()) {
this.logger.debug("Creating shared instance of singleton bean '" + beanName + "'");
}
this.beforeSingletonCreation(beanName);
boolean newSingleton = false;
boolean recordSuppressedExceptions = this.suppressedExceptions == null;
if (recordSuppressedExceptions) {
this.suppressedExceptions = new LinkedHashSet();
}
try {
//相当于调用 createBean() 方法
singletonObject = singletonFactory.getObject();
newSingleton = true;
} catch (IllegalStateException var16) {
singletonObject = this.singletonObjects.get(beanName);
if (singletonObject == null) {
throw var16;
}
} catch (BeanCreationException var17) {
BeanCreationException ex = var17;
if (recordSuppressedExceptions) {
Iterator var8 = this.suppressedExceptions.iterator();
while(var8.hasNext()) {
Exception suppressedException = (Exception)var8.next();
ex.addRelatedCause(suppressedException);
}
}
throw ex;
} finally {
if (recordSuppressedExceptions) {
this.suppressedExceptions = null;
}
this.afterSingletonCreation(beanName);
}
if (newSingleton) {
this.addSingleton(beanName, singletonObject);
}
}
return singletonObject != NULL_OBJECT ? singletonObject : null;
}
}
creatBean方法
protected Object createBean(String beanName, RootBeanDefinition mbd, Object[] args) throws BeanCreationException {
if (this.logger.isDebugEnabled()) {
this.logger.debug("Creating instance of bean '" + beanName + "'");
}
RootBeanDefinition mbdToUse = mbd;
Class<?> resolvedClass = this.resolveBeanClass(mbd, beanName, new Class[0]);
if (resolvedClass != null && !mbd.hasBeanClass() && mbd.getBeanClassName() != null) {
mbdToUse = new RootBeanDefinition(mbd);
mbdToUse.setBeanClass(resolvedClass);
}
try {
mbdToUse.prepareMethodOverrides();
} catch (BeanDefinitionValidationException var7) {
throw new BeanDefinitionStoreException(mbdToUse.getResourceDescription(), beanName, "Validation of method overrides failed", var7);
}
Object beanInstance;
try {
beanInstance = this.resolveBeforeInstantiation(beanName, mbdToUse);
if (beanInstance != null) {
return beanInstance;
}
} catch (Throwable var8) {
throw new BeanCreationException(mbdToUse.getResourceDescription(), beanName, "BeanPostProcessor before instantiation of bean failed", var8);
}
beanInstance = this.doCreateBean(beanName, mbdToUse, args);
if (this.logger.isDebugEnabled()) {
this.logger.debug("Finished creating instance of bean '" + beanName + "'");
}
return beanInstance;
}
doCreateBean:
完成了对bean 的加载，流程展开讨论
protected Object doCreateBean(final String beanName, final RootBeanDefinition mbd, Object[] args) {
BeanWrapper instanceWrapper = null;
if (mbd.isSingleton()) {
instanceWrapper = (BeanWrapper)this.factoryBeanInstanceCache.remove(beanName);
}
//调用构造方法创建bean的实例
if (instanceWrapper == null) {
//使用合适的实例化策略来创建新的实例：工厂方法、构造函数自动注入、简单初始化
instanceWrapper = this.createBeanInstance(beanName, mbd, args);
}
final Object bean = instanceWrapper != null ? instanceWrapper.getWrappedInstance() : null;
Class<?> beanType = instanceWrapper != null ? instanceWrapper.getWrappedClass() : null;
synchronized(mbd.postProcessingLock) {
if (!mbd.postProcessed) {
//处理bean的前置处理器， Autowired 注解正是通过此方法实现诸如类型的预解析。
this.applyMergedBeanDefinitionPostProcessors(mbd, beanType, beanName);
mbd.postProcessed = true;
}
}
//判断当前bean是否满足早期暴露到缓存对象中的条件
boolean earlySingletonExposure = mbd.isSingleton() && this.allowCircularReferences && this.isSingletonCurrentlyInCreation(beanName);
if (earlySingletonExposure) {
if (this.logger.isDebugEnabled()) {
this.logger.debug("Eagerly caching bean '" + beanName + "' to allow for resolving potential circular references");
}
//把我们的早期对象包装成一个singletonFactory对象 该对象提供了一个getObject方法,该方法内部调用getEarlyBeanReference方法
this.addSingletonFactory(beanName, new ObjectFactory<Object>() {
public Object getObject() throws BeansException {
return AbstractAutowireCapableBeanFactory.this.getEarlyBeanReference(beanName, mbd, bean);
}
});
}
Object exposedObject = bean;
try {
//给我们的属性进行赋值(调用set方法进行赋值)
this.populateBean(beanName, mbd, instanceWrapper);
if (exposedObject != null) {
exposedObject = this.initializeBean(beanName, exposedObject, mbd);
}
} catch (Throwable var17) {
if (var17 instanceof BeanCreationException && beanName.equals(((BeanCreationException)var17).getBeanName())) {
throw (BeanCreationException)var17;
}
throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Initialization of bean failed", var17);
}
if (earlySingletonExposure) {
Object earlySingletonReference = this.getSingleton(beanName, false);
/**
* 去缓存中获取到我们的对象 由于传递的allowEarlyReference 是false 要求只能在一级二级缓存中去获取
* 正常普通的bean(不存在循环依赖的bean) 创建的过程中，压根不会把三级缓存提升到二级缓存中
*/
if (earlySingletonReference != null) {
//经过后置处理的bean和早期的bean引用还相等的话(表示当前的bean没有被代理过)
if (exposedObject == bean) {
exposedObject = earlySingletonReference;
} else if (!this.allowRawInjectionDespiteWrapping && this.hasDependentBean(beanName)) {
String[] dependentBeans = this.getDependentBeans(beanName);
Set<String> actualDependentBeans = new LinkedHashSet(dependentBeans.length);
String[] var12 = dependentBeans;
int var13 = dependentBeans.length;
for(int var14 = 0; var14 < var13; ++var14) {
String dependentBean = var12[var14];
if (!this.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.");
}
}
}
}
try {
this.registerDisposableBeanIfNecessary(beanName, bean, mbd);
return exposedObject;
} catch (BeanDefinitionValidationException var16) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Invalid destruction signature", var16);
}
}
doCreatBean方法详解
createBeanInstance:调用构造函数创建对象
protected BeanWrapper createBeanInstance(String beanName, RootBeanDefinition mbd, Object[] args) {
/*
*因为一个类可能有多个构造函数，所以需要根据配置文件中配置的参数或者传入的参数确定最终调用的构造函*数。因为判断过程会比较消耗性能，
*所以Spring会将解析、确定好的构造函数缓存到BeanDefinition中的*resolvedConstructorOrFactoryMethod字段中。在下次创建相同bean的时候(多例)，
*会直接从RootBeanDefinition中的属性resolvedConstructorOrFactoryMethod缓存的值获取，避免再次解析
*/
Class<?> beanClass = this.resolveBeanClass(mbd, beanName, new Class[0]);
if (beanClass != null && !Modifier.isPublic(beanClass.getModifiers()) && !mbd.isNonPublicAccessAllowed()) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Bean class isn't public, and non-public access not allowed: " + beanClass.getName());
}
//工厂方法不为空则使工厂方法初始化策略 也就是bean的配置过程中设置了factory-method方法
else if (mbd.getFactoryMethodName() != null) {
return this.instantiateUsingFactoryMethod(beanName, mbd, args);
} else {
boolean resolved = false;
boolean autowireNecessary = false;
if (args == null) {
synchronized(mbd.constructorArgumentLock) {
if (mbd.resolvedConstructorOrFactoryMethod != null) {
resolved = true;
autowireNecessary = mbd.constructorArgumentsResolved;
}
}
}
if (resolved) {
return autowireNecessary ? this.autowireConstructor(beanName, mbd, (Constructor[])null, (Object[])null) : this.instantiateBean(beanName, mbd);
} else {
Constructor<?>[] ctors = this.determineConstructorsFromBeanPostProcessors(beanClass, beanName);
return ctors == null && mbd.getResolvedAutowireMode() != 3 && !mbd.hasConstructorArgumentValues() && ObjectUtils.isEmpty(args) ? this.instantiateBean(beanName, mbd) : this.autowireConstructor(beanName, mbd, ctors, args);
}
}
}
initializeBean
protected Object initializeBean(final String beanName, final Object bean, RootBeanDefinition mbd) {
//进行对象初始化操作调用initializeBean，这里会进行Aware接口进行方法的回调，然后调用Bean的后置处理器的Before方法（postProcessorsBeforeInitialization），然后Bean的初始化方法，最后调用Bean的后置处理器的After方法（PostProcessorsAfterInitialization）
if (System.getSecurityManager() != null) {
AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
AbstractAutowireCapableBeanFactory.this.invokeAwareMethods(beanName, bean);
return null;
}
}, this.getAccessControlContext());
} else {
this.invokeAwareMethods(beanName, bean);
}
Object wrappedBean = bean;
if (mbd == null || !mbd.isSynthetic()) {
wrappedBean = this.applyBeanPostProcessorsBeforeInitialization(bean, beanName);
}
try {
this.invokeInitMethods(beanName, wrappedBean, mbd);
} catch (Throwable var6) {
throw new BeanCreationException(mbd != null ? mbd.getResourceDescription() : null, beanName, "Invocation of init method failed", var6);
}
if (mbd == null || !mbd.isSynthetic()) {
wrappedBean = this.applyBeanPostProcessorsAfterInitialization(wrappedBean, beanName);
}
return wrappedBean;
}
参考博客：