spring中管理的Bean的创建流程

 

Spring的生命周期.

 

1.       容器启动，实例化所有实现了BeanFactoyPostProcessor接口的类。他会在任何普通Bean实例化之前加载.

2.       实例化剩下的Bean，对这些Bean进行依赖注入。

3.       如果Bean有实现BeanNameAware的接口那么对这些Bean进行调用

4.       如果Bean有实现BeanFactoryAware接口的那么对这些Bean进行调用

5.       如果Bean有实现ApplicationContextAware接口的那么对这些Bean进行调用

6.       如果配置有实现BeanPostProcessor的Bean，那么调用它的postProcessBeforeInitialization方法

7.       如果Bean有实现InitializingBean接口那么对这些Bean进行调用

8.       如果Bean配置有init属性，那么调用它属性中设置的方法

9.       如果配置有实现BeanPostProcessor的Bean，那么调用它的postProcessAfterInitialization方法

10.   Bean正常是使用

11.   调用DisposableBean接口的destory方法

12.   调用Bean定义的destory方法

 

如果从大体上区分值分只为四个阶段

1.       BeanFactoyPostProcessor实例化

2.       Bean实例化，然后通过某些BeanFactoyPostProcessor来进行依赖注入

3.       BeanPostProcessor的调用.Spring内置的BeanPostProcessor负责调用Bean实现的接口: BeanNameAware, BeanFactoryAware, ApplicationContextAware等等，等这些内置的BeanPostProcessor调用完后才会调用自己配置的BeanPostProcessor

4.       Bean销毁阶段

 

 

以上是自己总结的，没研究过源码，恐有误…作参考用

以下附上验证的代码：

package mislay;import org.springframework.beans.BeansException;import org.springframework.beans.factory.config.BeanFactoryPostProcessor;import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;public class BeanFactoryPostProcessorTest implements BeanFactoryPostProcessor {@Overridepublic void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {System.out.println("--------> begin BeanFactoryPostProcessorTest");String[] names = beanFactory.getBeanDefinitionNames();for (String name : names) {System.out.println("definition bean name:" + name);}System.out.println("<--------- end BeanFactoryPostProcessorTest");}}

 

package mislay;import org.springframework.beans.BeansException;import org.springframework.beans.factory.config.BeanPostProcessor;public class BeanPostProcessorTest implements BeanPostProcessor {@Overridepublic Object postProcessAfterInitialization(Object bean, String beanName)throws BeansException {System.out.println("call BeanPostProcessor interface postProcessAfterInitialization method; :" + beanName);return bean;}@Overridepublic Object postProcessBeforeInitialization(Object bean, String beanName)throws BeansException {System.out.println("call BeanPostProcessor interface postProcessBeforeInitialization method ::" + beanName);if(bean instanceof BeanTest) {System.out.println("bean instanceof BeanTest");}return bean;}}

 

package mislay;import org.springframework.beans.BeansException;import org.springframework.beans.factory.BeanFactory;import org.springframework.beans.factory.BeanFactoryAware;import org.springframework.beans.factory.BeanNameAware;import org.springframework.beans.factory.DisposableBean;import org.springframework.beans.factory.InitializingBean;import org.springframework.beans.factory.config.BeanPostProcessor;import org.springframework.context.ApplicationContext;import org.springframework.context.ApplicationContextAware;public class BeanTest implements InitializingBean, DisposableBean,BeanNameAware,

BeanFactoryAware,ApplicationContextAware {@Overridepublic void afterPropertiesSet() throws Exception {System.out.println("call InitializingBean interface");}@Overridepublic void destroy() throws Exception {// TODO Auto-generated method stubSystem.out.println("call DisposableBean interface");}public void _init() {System.out.println("call bean init method");}public void _destory() {System.out.println("call bean destory method");}public void setSomething(Object something) {System.out.println("DI call setSomething method");}public BeanTest() {System.out.println("BeanTest create");}@Overridepublic void setBeanName(String name) {// TODO Auto-generated method stubSystem.out.println("call BeanNameAware interface name is:" + name);}@Overridepublic void setBeanFactory(BeanFactory beanFactory) throws BeansException {// TODO Auto-generated method stubSystem.out.println("call BeanFactoryAware interface");}@Overridepublic void setApplicationContext(ApplicationContext applicationContext)throws BeansException {// TODO Auto-generated method stubSystem.out.println("call ApplicationContextAware interface");}}

 

 

package mislay;import org.springframework.context.ApplicationContext;import org.springframework.context.support.AbstractApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Test {public static void main(String[] args) {ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");((AbstractApplicationContext) context).registerShutdownHook();}}

 

//下面是输出的内容

//这一段可以看出首先实例化化的BeanFactoryPostProcessor--------> begin BeanFactoryPostProcessorTestdefinition bean name:mislay.BeanFactoryPostProcessorTestdefinition bean name:mislay.BeanPostProcessorTestdefinition bean name:beanTest<--------- end BeanFactoryPostProcessorTest//这一段是Bean的创建以及依赖注入BeanTest createDI call setSomething method//这一段就是内置的BeanPostProcessor调用call BeanNameAware interface name is:beanTestcall BeanFactoryAware interfacecall ApplicationContextAware interface//这里开始调用自己BeanPostProcessorcall BeanPostProcessor interface postProcessBeforeInitialization method ::beanTestbean instanceof BeanTest//穿插着对InitializingBean接口和定义的init方法的调用call InitializingBean interfacecall bean init methodcall BeanPostProcessor interface postProcessAfterInitialization method; :beanTest//上面就结束了对配置的BeanPostProcessor的调用//最后销毁call DisposableBean interfacecall bean destory method