關於在spring 容器初始化 bean 和銷燬前所做的操作定義方式有三種：

第一種：通過@PostConstruct 和 @PreDestroy 方法 實現初始化和銷燬bean之前進行的操作

第二種是：通過 在xml中定義init-method 和 destory-method方法

第三種是： 通過bean實現InitializingBean和 DisposableBean介面
下面演示通過 @PostConstruct 和 @PreDestory

1:定義相關的實現類：

package com.myapp.core.annotation.init;

import javax.annotation.PostConstruct;
import
 
 javax.annotation.PreDestroy;

public class PersonService {

    private String  message;

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    @PostConstruct
    public void  init(){
        System.out.println("I'm  init  method  using  @PostConstrut...."
 
+message);
    }

    @PreDestroy
    public void  dostory(){
        System.out.println("I'm  destory method  using  @PreDestroy....."+message);
    }

}

2：定義相關的配置檔案：

<?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-3.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.1.xsd">

<!-- <context:component-scan  base-package="com.myapp.core.jsr330"/> -->

<context:annotation-config />

<bean id="personService" class="com.myapp.core.annotation.init.PersonService">
  <property name="message" value="123"></property>
</bean>

</beans>

其中告訴spring 容器採用註解配置：掃描註解配置；

測試類：

package com.myapp.core.annotation.init;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MainTest {

    public static void main(String[] args) {

        ApplicationContext  context = new ClassPathXmlApplicationContext("resource/annotation.xml");

        PersonService   personService  =  (PersonService)context.getBean("personService");

        personService.dostory();
    }

}

測試結果：

I’m init method using @PostConstrut….123
I’m destory method using @PreDestroy…..123

其中也可以通過申明載入org.springframework.context.annotation.CommonAnnotationBeanPostProcessor

類來告訴Spring容器採用的 常用 註解配置的方式：

只需要修改配置檔案為：

<?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-3.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.1.xsd">

<!-- <context:component-scan  base-package="com.myapp.core.jsr330"/> -->

<!-- <context:annotation-config /> -->


<bean class="org.springframework.context.annotation.CommonAnnotationBeanPostProcessor" />
<bean id="personService" class="com.myapp.core.annotation.init.PersonService">
          <property name="message" value="123"></property>
</bean>



</beans>

第二種是：通過 在xml中定義init-method 和 destory-method方法
在xml中配置 init-method和 destory-method方法

只是定義spring 容器在初始化bean 和容器銷燬之前的所做的操作

基於xml的配置只是一種方式：

直接上xml中配置檔案:

   <bean id="personService" class="com.myapp.core.beanscope.PersonService" scope="singleton"  init-method="init"  destroy-method="cleanUp">

   </bean>

定義PersonService類：

package com.myapp.core.beanscope;


public class PersonService  {
   private String  message;

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }



    public void init(){
        System.out.println("init");
    }
    //  how  validate the  destory method is  a question
    public void  cleanUp(){
        System.out.println("cleanUp");
    }
}

相應的測試類：

package com.myapp.core.beanscope;

import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MainTest {
  public static void main(String[] args) {

      AbstractApplicationContext  context =new  ClassPathXmlApplicationContext("SpringBeans.xml");

    PersonService  person = (PersonService)context.getBean("personService");

    person.setMessage("hello  spring");

    PersonService  person_new = (PersonService)context.getBean("personService");

    System.out.println(person.getMessage());
    System.out.println(person_new.getMessage());
    context.registerShutdownHook();


}
} 

測試結果：

init
hello spring
hello spring
cleanUp

可以看出 init 方法和 clean up方法都已經執行了。
context.registerShutdownHook(); 是一個鉤子方法，當jvm關閉退出的時候會呼叫這個鉤子方法，在設計模式之 模板模式中 通過在抽象類中定義這樣的鉤子方法由實現類進行實現，這裡的實現類是AbstractApplicationContext，這是spring 容器優雅關閉的方法。

第三種是： 通過bean實現InitializingBean和 DisposableBean介面
1：定義相應類實現InitializingBean ,DisposableBean 介面

package com.myapp.core.annotation.init;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;

import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;

public class PersonService  implements InitializingBean,DisposableBean{

    private String  message;

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    @Override
    public void destroy() throws Exception {
        // TODO Auto-generated method stub
        System.out.println("I'm  init  method  using implements InitializingBean interface...."+message);

    }

    @Override
    public void afterPropertiesSet() throws Exception {
        // TODO Auto-generated method stub
        System.out.println("I'm  init  method  using implements DisposableBean interface...."+message);

    }


}

2：定義相應的配置檔案:

<?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-3.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.1.xsd">

<!-- <context:component-scan  base-package="com.myapp.core.jsr330"/> -->

<!-- <context:annotation-config /> -->


<!-- <bean class="org.springframework.context.annotation.CommonAnnotationBeanPostProcessor" />
<bean id="personService" class="com.myapp.core.annotation.init.PersonService">
          <property name="message" value="123"></property>
</bean>
 -->

<bean id="personService" class="com.myapp.core.annotation.init.PersonService">
          <property name="message" value="123"></property>
</bean>

</beans>

3：測試類：

package com.myapp.core.annotation.init;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MainTest {

    public static void main(String[] args) {

        AbstractApplicationContext  context = new ClassPathXmlApplicationContext("resource/annotation.xml");

        PersonService   personService  =  (PersonService)context.getBean("personService");

             context.registerShutdownHook();
    }

}

4：輸出測試結果：

I'm  init  method  using implements DisposableBean interface....123
三月 16, 2013 5:06:34 下午 org.springframework.context.support.AbstractApplicationContext doClose
INFO: Closing org[email protected]205756: startup date [Sat Mar 16 17:06:30 CST 2013]; root of context hierarchy
I'm  init  method  using implements InitializingBean interface....123