深入理解Spring中bean的生命周期

时间:2021-05-22 19:41:30

[Spring中bean的生命周期]


深入理解Spring中bean的生命周期

bean的生命周期

1.以ApplocationContext上下文单例模式装配bean为例,深入探讨bean的生命周期:

 (1).生命周期图:

深入理解Spring中bean的生命周期

  (2).具体事例:

  person类实现BeanNameAware,BeanFactoryAware接口

 public class Person implements BeanNameAware ,BeanFactoryAware{

     private String name;

     public Person(){
System.out.println("调用构造器为属性值初始化");
} public String getName() {
return name;
} public void setName(String name) {
this.name = name;
} @Override
public void setBeanName(String arg0) {
// TODO Auto-generated method stub
System.out.println("获取beanName id值"+" "+arg0); } @Override
public void setBeanFactory(BeanFactory arg0) throws BeansException {
// TODO Auto-generated method stub
System.out.println("获取BeanFactory" +" "+arg0); } }
 public class MyBeanPostProcessor  implements BeanPostProcessor{

     @Override
public Object postProcessAfterInitialization(Object arg0, String arg1) throws BeansException {
// TODO Auto-generated method stub
System.out.println("调用postProcessAfterInitialization");
return arg0;
} @Override
public Object postProcessBeforeInitialization(Object arg0, String arg1) throws BeansException {
// TODO Auto-generated method stub
System.out.println("调用postProcessBeforeInitialization");
return arg0;
} }

ApplicationContext.xml配置文件:

 <?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<!-- bean的配置文件 -->
<bean id="person" class="org.jingdong.bean.life.Person">
<property name="name" value="grl"></property>
</bean> <bean id="myBeanPostProcessor" class="org.jingdong.bean.life.MyBeanPostProcessor"></bean>
</beans>

Main.java

 public class Main {
public static void main(String[] args) {
// 创建IOC容器
ApplicationContext ac = new ClassPathXmlApplicationContext("org/jingdong/bean/life/applicationContext.xml");
//从容器中获取bean实例
Person person = (Person) ac.getBean("person");
//使用bean
System.out.println(person.getName());
}
}

 

2.以Spring Factory装配bean为例:

  (1).生命周期图:

  深入理解Spring中bean的生命周期