深入理解Spring中bean的生命周期

[Spring中bean的生命周期]

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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：

　　（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：