去字节面试，直接让人出门左拐：Bean 生命周期都不知道！

spring启动创建bean流程 

 

 

 

 

 

下面就接上了 

bean生命周期 

 

doGetBean

Object sharedInstance = this.getSingleton(beanName);

sharedInstance = this.getSingleton(beanName, new ObjectFactory<Object>() {
    public Object getObject() throws BeansException {

beanInstance = this.doCreateBean(beanName, mbdToUse, args);

主要步骤

getBean->doGetBean->getSingleton这个逻辑，我们着重关注一下getSingleton方法的实现

属性赋值

this.populateBean(beanName, mbd, instanceWrapper);

初始化
exposedObject = this.initializeBean(beanName, exposedObject, mbd);

Object earlySingletonReference = this.getSingleton(beanName, false);