Spring Bean的生命周期

一、生命周期流程图

Spring Bean的完整生命周期从创建Spring容器开始，直到最终Spring容器销毁Bean，这其中包含了一系列关键点：

二、Bean的完整生命周期经历了各种方法调用，这些方法可以划分为以下几类：

1、Bean自身的方法：这个包括了Bean本身调用的方法和通过配置文件中<bean>的init-method和destroy-method指定的方法

2、Bean级生命周期接口方法：这个包括了BeanNameAware、BeanFactoryAware、ApplicationContextAware、InitializingBean和DiposableBean这些接口的方法

3、容器级生命周期接口方法：这个包括了InstantiationAwareBeanPostProcessor 和 BeanPostProcessor 这两个接口实现，一般称它们的实现类为“后处理器”。

4、工厂后处理器接口方法：这个包括了AspectJWeavingEnabler, ConfigurationClassPostProcessor, CustomAutowireConfigurer等等非常有用的工厂后处理器　　接口的方法。工厂后处理器也是容器级的。在应用上下文装配配置文件之后立即调用。

三、示例代码

自定义Bean实现BeanNameAware,BeanFactoryAware,ApplicationContextAware,InitializingBean,DisposableBean接口

package com.cuisea.lifecycle;import org.springframework.beans.BeansException;import org.springframework.beans.factory.*;import org.springframework.context.ApplicationContext;import org.springframework.context.ApplicationContextAware;/** * Bean生命周期 */public class Person implements BeanNameAware,BeanFactoryAware,ApplicationContextAware,InitializingBean,DisposableBean {    private String name;    private String beanName;    private BeanFactory beanFactory;    private ApplicationContext applicationContext;    public Person() {        System.out.println("【构造器】调用Person的构造器实例化");    }    public void setName(String name) {        this.name = name;        System.out.println("【注入属性】注入属性name");    }    @Override    public void setBeanFactory(BeanFactory beanFactory) throws BeansException {        this.beanFactory=beanFactory;        System.out.println("【BeanFactoryAware接口】调用BeanFactoryAware.setBeanFactory()");    }    @Override    public void setBeanName(String beanName) {        this.beanName=beanName;        System.out.println("【BeanNameAware接口】调用BeanNameAware.setBeanName()");    }    @Override    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {        this.applicationContext=applicationContext;        System.out.println("【ApplicationContextAware接口】调用ApplicationContextAware.setApplicationContext()");    }    @Override    public void destroy() throws Exception {        System.out.println("【DiposibleBean接口】调用DiposibleBean.destory()");    }    @Override    public void afterPropertiesSet() throws Exception {        System.out.println("【InitializingBean接口】调用InitializingBean.afterPropertiesSet()");    }    // 通过<lifecycle>的init-method属性指定的初始化方法    public void initMethod() {        System.out.println("【init-method】调用<lifecycle>的init-method属性指定的初始化方法");    }    // 通过<lifecycle>的destroy-method属性指定的初始化方法    public void destroyMethod() {        System.out.println("【destroy-method】调用<lifecycle>的destroy-method属性指定的初始化方法");    }}

BeanFactoryPostProcessor接口实现类：

package com.cuisea.lifecycle;import org.springframework.beans.BeansException;import org.springframework.beans.factory.config.BeanDefinition;import org.springframework.beans.factory.config.BeanFactoryPostProcessor;import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;public class MyBeanFactoryPostProcessor implements BeanFactoryPostProcessor {    public MyBeanFactoryPostProcessor() {        System.out.println("这是BeanFactoryPostProcessor实现类构造器！！");    }    @Override    public void postProcessBeanFactory(ConfigurableListableBeanFactory configurableListableBeanFactory) throws BeansException {        System.out.println("BeanFactoryPostProcessor调用postProcessBeanFactory方法");        BeanDefinition bd = configurableListableBeanFactory.getBeanDefinition("person");        bd.getPropertyValues().addPropertyValue("name", "test");    }}

BeanPostProcessor接口实现类：

package com.cuisea.lifecycle;import org.springframework.beans.BeansException;import org.springframework.beans.factory.config.BeanPostProcessor;public class MyBeanPostProcessor implements BeanPostProcessor {    public MyBeanPostProcessor() {        System.out.println("这是BeanPostProcessor实现类构造器！！");    }    @Override    public Object postProcessBeforeInitialization(Object o, String s) throws BeansException {        System.out.println("BeanPostProcessor接口方法postProcessBeforeInitialization对属性进行更改！");        return o;    }    @Override    public Object postProcessAfterInitialization(Object o, String s) throws BeansException {        System.out.println("BeanPostProcessor接口方法postProcessAfterInitialization对属性进行更改！");        return o;    }}

InstantiationAwareBeanPostProcessor接口实现类：

package com.cuisea.lifecycle;import org.springframework.beans.BeansException;import org.springframework.beans.PropertyValues;import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessorAdapter;import java.beans.PropertyDescriptor;public class MyInstantiationAwareBeanPostProcessor extends InstantiationAwareBeanPostProcessorAdapter {    public MyInstantiationAwareBeanPostProcessor() {        super();        System.out.println("这是InstantiationAwareBeanPostProcessorAdapter实现类构造器！！");    }    // 接口方法、实例化Bean之前调用    @Override    public Object postProcessBeforeInstantiation(Class beanClass,String beanName) throws BeansException {        System.out.println("InstantiationAwareBeanPostProcessor调用postProcessBeforeInstantiation方法");        return null;    }    // 接口方法、实例化Bean之后调用    @Override    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {        System.out.println("InstantiationAwareBeanPostProcessor调用postProcessAfterInitialization方法");        return bean;    }    // 接口方法、设置某个属性时调用    @Override    public PropertyValues postProcessPropertyValues(PropertyValues var1, PropertyDescriptor[] var2, Object var3, String var4) throws BeansException{        System.out.println("InstantiationAwareBeanPostProcessor调用postProcessPropertyValues方法");        return var1;    }}

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"       xmlns:context="http://www.springframework.org/schema/context"       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">    <bean id="beanPostProcessor" class="com.cuisea.lifecycle.MyBeanPostProcessor"/>    <bean id="instantiationAwareBeanPostProcessor" class="com.cuisea.lifecycle.MyInstantiationAwareBeanPostProcessor"/>    <bean id="beanFactoryPostProcessor" class="com.cuisea.lifecycle.MyBeanFactoryPostProcessor"/>    <bean id="person" class="com.cuisea.lifecycle.Person" init-method="initMethod" destroy-method="destroyMethod" scope="singleton">        <property name="name" value="cuisea"/>    </bean></beans>

测试代码：

package com.cuisea;import com.cuisea.lifecycle.Person;import org.springframework.context.support.ClassPathXmlApplicationContext;import java.util.concurrent.TimeUnit;public class LifeCycleTest {    public static void main(String[] args) {        ClassPathXmlApplicationContext context=new ClassPathXmlApplicationContext("applicationContext.xml");        System.out.println("Spring容器初始化成功");        Person person=(Person)context.getBean("person");        System.out.println(person);        try {            TimeUnit.SECONDS.sleep(5);        } catch (InterruptedException e) {            e.printStackTrace();        }        System.out.println("Spring容器开始关闭");        context.close();    }}

运行结果：

参考：http://www.cnblogs.com/zrtqsk/p/3735273.html 流程中增加了ApplicationContextAware接口