一四康、生命周期流程圖：

Spring Bean的完整生命周期從創(chuàng)建Spring容器開始幔嫂，直到最終Spring容器銷毀Bean透罢，這其中包含了一系列關(guān)鍵點(diǎn)

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假設(shè)一個(gè)Bean實(shí)現(xiàn)了所有的接口户矢，大的概況一下Bean的生命周期：

1.實(shí)例化BeanFactoryPostProcessor：處理的對(duì)象是BeanFactory級(jí)別

2.實(shí)例化BeanPostProcessor實(shí)現(xiàn)類

3.實(shí)例化InstantiationAwareBeanPostProcessorAdapter實(shí)現(xiàn)類，注：該類是BeanPostProcessor的擴(kuò)展

4.執(zhí)行InstantiationAwareBeanPostProcessorAdapter類的postProcessBeforeInstantiation方法

5.Bean的構(gòu)造方法

6.執(zhí)行InstantiationAwareBeanPostProcessorAdapter類的postProcessPropertyValues

7.為Bean注入屬性扫茅，即依賴注入

8.調(diào)用BeanNameAware的setBeanName方法

9.調(diào)用BeanNameAware的setBeanFactory方法

10.執(zhí)行BeanPostProcessor的后置處理器蹋嵌，postProcessAfterInitialization方法

11.調(diào)用InitializingBean的afterPropertiesSet方法

12.調(diào)用bean的init-method初始化方法

13.執(zhí)行BeanPostProcessor的postProcessAfterInitialization

14.執(zhí)行InstantiationAwareBeanPostProcessorAdapter的后置方法育瓜，postProcessAfterInitialization

15.Bean的使用

16.調(diào)用DiposibleBean的destory方法

17.調(diào)用bean指定的destory-method方法

為了上述流程的正確性葫隙，我們可以用代碼來測(cè)試一下：

測(cè)試Bean - StudentBean類：

測(cè)試Bean - StudentBean類：

/**

• 測(cè)試生命周期的Bean

• Created by kxm
  */
  public class StudentBean implements InitializingBean, DisposableBean, BeanNameAware, BeanFactoryAware {
  private String name;
  private int age;

  private String beanName; //實(shí)現(xiàn)了BeanNameAware接口，Spring可以將BeanName注入該屬性中
  private BeanFactory beanFactory; //實(shí)現(xiàn)了BeanFactory接口躏仇，Spring可將BeanFactory注入該屬性中

  public StudentBean(){
  System.out.println("【Bean構(gòu)造方法】學(xué)生類的無參構(gòu)造方法");
  }

  @Override
  public String toString() {
  return "StudentBean{" +
  "name='" + name + ''' +
  ", age=" + age +
  ", beanName='" + beanName + ''' +
  '}';
  }

  public String getName() {
  return name;
  }

  public void setName(String name) {
  System.out.println("【set注入】注入學(xué)生的name屬性");
  this.name = name;
  }

  public int getAge() {
  return age;
  }

  public void setAge(int age) {
  System.out.println("【set注入】注入學(xué)生的age屬性");
  this.age = age;
  }

  /**

  • 自己編寫的初始化方法
    */
    public void myInit(){
    System.out.println("【init-method】調(diào)用init-method屬性配置的初始化方法");
    }

  /**

  • 自己編寫的銷毀方法
    */
    public void myDestroy(){
    System.out.println("【destroy-method】調(diào)用destroy-method屬性配置的銷毀方法");
    }

  /**

  • BeanFactoryAware接口的方法
  • @param beanFactory
  • @throws BeansException
    */
    public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
    this.beanFactory = beanFactory;
    System.out.println("【BeanFactoryAware接口】調(diào)用BeanFactoryAware的setBeanFactory方法得到beanFactory引用");
    }

  /**

  • BeanNameAware接口的方法
  • @param name
    */
    public void setBeanName(String name) {
    this.beanName = name;
    System.out.println("【BeanNameAware接口】調(diào)用BeanNameAware的setBeanName方法得到Bean的名稱");
    }

  /**

  • InitializingBean接口的方法
  • @throws Exception
    */
    public void afterPropertiesSet() throws Exception {
    System.out.println("【InitializingBean接口】調(diào)用InitializingBean接口的afterPropertiesSet方法");
    }

  /**

  • DisposableBean接口的方法
  • @throws Exception
    */
    public void destroy() throws Exception {
    System.out.println("【DisposableBean接口】調(diào)用DisposableBean接口的destroy方法");
    }
    }
    MyBeanFactoryPostProcessor工廠處理器類：

public class MyBeanFactoryPostProcessor implements BeanFactoryPostProcessor {

public MyBeanFactoryPostProcessor() {
    System.out.println("【BeanFactoryPostProcessor接口】調(diào)用BeanFactoryPostProcessor實(shí)現(xiàn)類構(gòu)造方法");
}

/**
 * 重寫B(tài)eanFactoryPostProcessor接口的postProcessBeanFactory方法恋脚，可通過該方法對(duì)beanFactory進(jìn)行設(shè)置
 */
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory)
        throws BeansException {
    System.out.println("【BeanFactoryPostProcessor接口】調(diào)用BeanFactoryPostProcessor接口的postProcessBeanFactory方法");
}

}
MyInstantiationAwareBeanPostProcessor類：

/**

• 一般情況下，當(dāng)我們需要實(shí)現(xiàn)InstantiationAwareBeanPostProcessor接口時(shí)焰手，是通過繼承Spring框架中InstantiationAwareBeanPostProcessor接口實(shí)現(xiàn)類

• InstantiationAwareBeanPostProcessorAdapter這個(gè)適配器類來簡(jiǎn)化我們實(shí)現(xiàn)接口的工作
  */
  public class MyInstantiationAwareBeanPostProcessor extends InstantiationAwareBeanPostProcessorAdapter {

  public MyInstantiationAwareBeanPostProcessor() {
  System.out.println("【InstantiationAwareBeanPostProcessor接口】調(diào)用InstantiationAwareBeanPostProcessor構(gòu)造方法");
  }

  /**

  • 實(shí)例化Bean之前調(diào)用
    */
    public Object postProcessBeforeInstantiation(Class beanClass, String beanName) throws BeansException {
    System.out.println("【InstantiationAwareBeanPostProcessor接口】調(diào)用InstantiationAwareBeanPostProcessor接口的postProcessBeforeInstantiation方法");
    return null;
    }

  /**

  • 實(shí)例化Bean之后調(diào)用
    */
    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
    System.out.println("【InstantiationAwareBeanPostProcessor接口】調(diào)用InstantiationAwareBeanPostProcessor接口的postProcessAfterInitialization方法");
    return bean;
    }

  /**

  • 設(shè)置某個(gè)屬性時(shí)調(diào)用
    */
    public PropertyValues postProcessPropertyValues(PropertyValues pvs, PropertyDescriptor[] pds, Object bean, String beanName)
    throws BeansException {
    System.out.println("【InstantiationAwareBeanPostProcessor接口】調(diào)用InstantiationAwareBeanPostProcessor接口的postProcessPropertyValues方法");
    return pvs;
    }
    }
    MyBeanPostProcessor類：

/**

• Created by kxm
  */
  public class MyBeanPostProcessor implements BeanPostProcessor {

  public MyBeanPostProcessor(){
  System.out.println("【BeanPostProcessor接口】調(diào)用BeanPostProcessor的構(gòu)造方法");
  }

  public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
  System.out.println("【BeanPostProcessor接口】調(diào)用postProcessBeforeInitialization方法糟描，這里可對(duì)"+beanName+"的屬性進(jìn)行更改。");
  return bean;
  }

  public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
  System.out.println("【BeanPostProcessor接口】調(diào)用postProcessAfterInitialization方法书妻，這里可對(duì)"+beanName+"的屬性進(jìn)行更改船响。");
  return bean;
  }
  }
  XML配置：

<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"
xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd">

<!-- 生命周期測(cè)試  -->
<!--配置Bean的后置處理器-->
<bean id="beanPostProcessor" class="com.my.spring.life.MyBeanPostProcessor">
</bean>

<!--配置instantiationAwareBeanPostProcessor-->
<bean id="instantiationAwareBeanPostProcessor" class="com.my.spring.life.MyInstantiationAwareBeanPostProcessor">
</bean>

<!--配置BeanFactory的后置處理器-->
<bean id="beanFactoryPostProcessor" class="com.my.spring.life.MyBeanFactoryPostProcessor">
</bean>

<bean id="studentBean" class="com.my.spring.life.StudentBean" init-method="myInit"
      destroy-method="myDestroy" scope="singleton">
    <property name="name" value="yanxiao"></property>
    <property name="age" value="21"></property>
</bean>

</beans>
測(cè)試類：

public class TestCyclelife {

/**
 * Created by yanxiao on 2016/8/1.
 */
public static void main(String[] args){
    System.out.println("--------------【初始化容器】---------------");

    ApplicationContext context = new ClassPathXmlApplicationContext("Springlife.xml");
    System.out.println("-------------------【容器初始化成功】------------------");
    //得到studentBean，并顯示其信息
    StudentBean studentBean = context.getBean("studentBean",StudentBean.class);
    System.out.println(studentBean);

    System.out.println("--------------------【銷毀容器】----------------------");
    ((ClassPathXmlApplicationContext)context).registerShutdownHook();
}

}

image

符合上述的Bean的生命周期躲履，至此见间，Bean的生命周期問題已基本解決，不過還等待著你繼續(xù)去深入工猜。