Bean的生命周期

更新时间：2022-10-04 21:09:52

1、实现各种生命周期控制访问的NewCar

package com.beanprocess;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.*;
/**
 * Created by gao on 16-3-18.
 */
public class NewCar implements BeanFactoryAware,BeanNameAware,InitializingBean,
        DisposableBean{
    private String brand;
    private String color;
    private int maxSpeed;
    private BeanFactory beanFactory;
    private String beanName;
    public NewCar() {
        System.out.println("调用NewCar()构造函数");
    }
    public NewCar(String brand, String color, int maxSpeed) {
        this.brand = brand;
        this.color = color;
        this.maxSpeed = maxSpeed;
    }
    public String getBrand() {
        return brand;
    }
    public void setBrand(String brand) {
        System.out.println("调用setBrand()设置属性");
        this.brand = brand;
    }
    public String getColor() {
        return color;
    }
    public void setColor(String color) {
        this.color = color;
    }
    public int getMaxSpeed() {
        return maxSpeed;
    }
    public void setMaxSpeed(int maxSpeed) {
        this.maxSpeed = maxSpeed;
    }
    public void introduce() {
        System.out.println("brand:" + brand + ";color:" + color + ";maxSpeed:" + maxSpeed);
    }
    @Override
    public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
        System.out.println("调用BeanFactoryAware.setBeanFactory().");
        this.beanFactory = beanFactory;
    }
    @Override
    public void setBeanName(String beanName) {
        System.out.println("调用BeanNameAware.setBeanName().");
        this.beanName = beanName;
    }
    @Override
    public void destroy() throws Exception {
        System.out.println("调用DisposableBean.destroy().");
    }
    @Override
    public void afterPropertiesSet() throws Exception {
        System.out.println("调用InitializingBean.afterPropertiesSet()。");
    }
    public void myInit(){
        System.out.println("调用init-method所指定的myInit()，将maxSpeed设置为350.");
        this.maxSpeed = 350;
    }
    public void myDestory(){
        System.out.println("调用destory-method所指定的myDestory()。");
    }
}

2、InstantiationAwareBeanPostProcessor实现类

package com.beanprocess;
import org.springframework.beans.BeansException;
import org.springframework.beans.PropertyValues;
import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessorAdapter;
import java.beans.PropertyDescriptor;
/**
 * Created by gao on 16-3-18.
 */
public class MyInstantiationAwareBeanPostProcessor extends InstantiationAwareBeanPostProcessorAdapter {
    public Object postProcessBeforeInstantiation(Class beanClass, String beanName) throws BeansException {
        if ("newCar".equals(beanName)) {
            System.out.println("InstantiationAware BeanPostProcessor.postProcessBeforeInstantiation");
        }
        return null;
    }
    public boolean postProcessAfterInstantiation(Object bean, String beanName) throws BeansException {
        if("newCar".equals(beanName)){
            System.out.println("InstantiationAwareBeanPostProcessor.postProcessAfterInstantiation");
        }
        return true;
    }
    public PropertyValues postProcessPropertyValues(
            PropertyValues pvs, PropertyDescriptor[] pds, Object bean, String beanName)
            throws BeansException {
        if("newCar".equals(beanName)){
            System.out.println("InstantiationAwareBeanPostProcessor.postProcessPropertyValues");
        }
        return pvs;
    }
    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
        return bean;
    }
    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
        return bean;
    }
}

3、BeanPostProcessor实现类

package com.beanprocess;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
/**
 * Created by gao on 16-3-18.
 */
public class MyBeanPostProcessor  implements BeanPostProcessor{
    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
        if(beanName.equals("newCar")){
            NewCar newCar = (NewCar)bean;
            if(newCar.getMaxSpeed() >= 350){
                System.out.println("调用MyBeanPostProcessor.postProcessAfterInitialization()，将maxSpeed调整为350。");
                newCar.setMaxSpeed(350);
            }
        }
        return bean;
    }
    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
        if(beanName.equals("newCar")){
            NewCar newCar = (NewCar)bean;
            if(newCar.getColor() == null){
                System.out.println("调用MyBeanPostProcessor.postProcessBeforeInitialization()，color为空，设置为默认黑色。");
                newCar.setColor("黑色");
            }
        }
        return bean;
    }
}

4、工厂后处理器：MyBeanFactoryPostProcessor.java

package com.beanprocess;
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;
/**
 * Created by gao on 16-3-18.
 */
public class MyBeanFactoryPostProcessor implements BeanFactoryPostProcessor {
    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory bf) throws BeansException {
        BeanDefinition bd = bf.getBeanDefinition("newCar");
        bd.getPropertyValues().addPropertyValue("brand", "奇瑞QQ");
        System.out.println("调用MyBeanFactoryPostProcessor.postProcessBeanFactory()！");
    }
}

5、beans.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:p="http://www.springframework.org/schema/p"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">
    <bean id="newCar" class="com.beanprocess.NewCar"
          init-method="myInit"
          destroy-method="myDestory"
          p:brand="迈锐宝"
          p:color="黑色"
          p:maxSpeed="300"
       />
    <bean id="myBeanPostProcessor" class="com.beanprocess.MyBeanPostProcessor"/>
    <bean id="myBeanFactoryPostProcessor" class="com.beanprocess.MyBeanFactoryPostProcessor"/>
</beans>

5、测试类：BeanLifeCycle

package com.beanprocess;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.beans.factory.xml.XmlBeanFactory;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
/**
 * Created by gao on 16-3-18.
 */
public class BeanLifeCycle {
    private static void LifeCycleInBeanFactory(){
        Resource res = new ClassPathResource("beans.xml");
        BeanFactory bf = new XmlBeanFactory(res);
        (new MyBeanFactoryPostProcessor()).postProcessBeanFactory((XmlBeanFactory)bf);
        //InstantiationAwareBeanPostProcessor
       // ((ConfigurableBeanFactory)bf).addBeanPostProcessor(new MyInstantiationAwareBeanPostProcessor());
        //BeanPostProcessor
       // ((ConfigurableBeanFactory)bf).addBeanPostProcessor(new MyBeanPostProcessor());
        NewCar newCar1 = (NewCar)bf.getBean("newCar");
        newCar1.introduce();
        newCar1.setColor("红色");
        NewCar newCar2 = bf.getBean("newCar",NewCar.class);
        newCar2.introduce();
        ((XmlBeanFactory)bf).destroySingletons();
    }
    public static void main(String[] args) {
        LifeCycleInBeanFactory();
    }
}

输出结果：

2016-03-18 20:10:42,648 INFO [main] (XmlBeanDefinitionReader.java:315) - Loading XML bean definitions from class path resource [beans.xml]

调用MyBeanFactoryPostProcessor.postProcessBeanFactory()！

调用NewCar()构造函数

调用setBrand()设置属性

调用BeanNameAware.setBeanName().

调用BeanFactoryAware.setBeanFactory().

调用InitializingBean.afterPropertiesSet()。

调用init-method所指定的myInit()，将maxSpeed设置为350.

brand:奇瑞QQ;color:黑色;maxSpeed:350

brand:奇瑞QQ;color:红色;maxSpeed:350

2016-03-18 20:10:43,251 INFO [main] (DefaultSingletonBeanRegistry.java:422) - Destroying singletons in org.springframework.beans.factory.xml.XmlBeanFactory@55782201: defining beans [newCar,myBeanPostProcessor,myBeanFactoryPostProcessor]; root of factory hierarchy

调用DisposableBean.destroy().

调用destory-method所指定的myDestory()。

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Bean的生命周期

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