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生命周期过程

• 如果容器注册InstantiationAwareBeanPostProcessor接口，调用postProcessBeforeInstantiation方法
• Bean的实例化(调用默认构造器)
• 如果容器注册InstantiationAwareBeanPostProcessor接口，调用postProcessAfterInstantiation方法
• 如果容器注册InstantiationAwareBeanPostProcessor接口，调用postProcessPropertyValues方法
• 根据配置设置属性值
• 如果Bean实现了BeanNameAware接口，调用BeanNameAware接口的setBeanName方法
• 如果Bean实现了BeanFactoryAware 接口，调用BeanFactoryAware 接口的setBeanFactory方法
• 如果容器注册了BeanPostProcessor接口，调用BeanPostProcessor接口的postProcessBeforeInitialization方法
• 如果Bean实现了InitializingBean接口，调用InitializingBean接口的afterPropertiesSet方法
• 通过init-method属性配置的初始方法
• 如果容器注册了BeanPostProcessor接口，调用BeanPostProcessor接口的postProcessAfterInitialization 方法
• 如果是单例模式，将Bean放入缓存池中；容器销毁时，调用DisposableBean的destroy方法；最后调用destroy-method方法
• 如果是多例模式，将Bean交给调用者。

测试

package exa.ydoing.spring;import org.springframework.beans.factory.BeanFactory;import org.springframework.beans.factory.config.ConfigurableBeanFactory;import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessor;import org.springframework.beans.factory.xml.XmlBeanFactory;import org.springframework.core.io.ClassPathResource;import org.springframework.core.io.Resource;public class App {    public static void main(String[] args) {        //实例化BeanFactory        Resource res = new ClassPathResource("ApplicationContext.xml");        BeanFactory bf = new XmlBeanFactory(res);        //注册InstantiationAwareBeanPostProcessor后置处理器，因为InstantiationAwareBeanPostProcessor继承了BeanPostProcessor，        //所以不再单独注册BeanPostProcessor后置处理器        ((ConfigurableBeanFactory)bf).addBeanPostProcessor(new MyInstantiationAwareBeanPostProcessor());        //获得bean        MyBean bean = bf.getBean("myBean", MyBean.class);        bean.printName();        //销毁所有Bean        ((XmlBeanFactory)bf).destroySingletons();    }}

InstantiationAwareBeanPostProcessor 的实现：

package exa.ydoing.spring;import java.beans.PropertyDescriptor;import org.springframework.beans.BeansException;import org.springframework.beans.PropertyValues;import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessor;public class MyInstantiationAwareBeanPostProcessor implements InstantiationAwareBeanPostProcessor {
       @Override    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {        // TODO Auto-generated method stub        System.out.println("调用BeanPostProcessor接口的postProcessBeforeInitialization方法");        return bean;    }    @Override    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {        // TODO Auto-generated method stub        System.out.println("调用BeanPostProcessor接口的postProcessAfterInitialization方法");        return bean;    }    @Override    public Object postProcessBeforeInstantiation(Class
    beanClass, String beanName) throws BeansException {        // TODO Auto-generated method stub        System.out.println("调用InstantiationAwareBeanPostProcessor接口的postProcessBeforeInstantiation方法");        return null;    }    @Override    public boolean postProcessAfterInstantiation(Object bean, String beanName) throws BeansException {        // TODO Auto-generated method stub        System.out.println("调用InstantiationAwareBeanPostProcessor接口的postProcessAfterInstantiation方法");        return true;    }    @Override    public PropertyValues postProcessPropertyValues(PropertyValues pvs, PropertyDescriptor[] pds, Object bean,            String beanName) throws BeansException {        // TODO Auto-generated method stub        System.out.println("调用InstantiationAwareBeanPostProcessor接口的postProcessPropertyValues方法");        return pvs;    }}

MyBean的代码：

package exa.ydoing.spring;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;public class MyBean implements BeanNameAware, BeanFactoryAware, InitializingBean, DisposableBean{
       private BeanFactory beanFactory;    private String name;    private String tag;    public MyBean(){        System.out.println("调用构造器实例化Bean");    }    public void printName(){        System.out.println("MyBean name is: " + name);    }    public String getTag() {        return tag;    }    public void setTag(String tag) {        this.tag = tag;        System.out.println("设置Bean的属性为：" + tag);    }    @Override    public void destroy() throws Exception {        // TODO Auto-generated method stub        System.out.println("调用DisposableBean接口的destroy方法");    }    @Override    public void afterPropertiesSet() throws Exception {        // TODO Auto-generated method stub        System.out.println("调用InitializingBean接口的afterPropertiesSet方法");    }    @Override    public void setBeanFactory(BeanFactory beanFactory) throws BeansException {        // TODO Auto-generated method stub        this.beanFactory = beanFactory;        System.out.println("调用BeanFactoryAware接口的setBeanFactory方法");    }    @Override    public void setBeanName(String name) {        // TODO Auto-generated method stub        this.name = name;        System.out.println("调用BeanNameAware接口的setBeanName方法");    }}

Bean的配置很简单：

输出：

调用InstantiationAwareBeanPostProcessor接口的postProcessBeforeInstantiation方法调用构造器实例化Bean调用InstantiationAwareBeanPostProcessor接口的postProcessAfterInstantiation方法调用InstantiationAwareBeanPostProcessor接口的postProcessPropertyValues方法设置Bean的属性为：test调用BeanNameAware接口的setBeanName方法调用BeanFactoryAware接口的setBeanFactory方法调用BeanPostProcessor接口的postProcessBeforeInitialization方法调用InitializingBean接口的afterPropertiesSet方法调用BeanPostProcessor接口的postProcessAfterInitialization方法MyBean name is: myBean调用DisposableBean接口的destroy方法

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