通过Spring @PostConstruct 和 @PreDestroy 方法 实现初始化和销毁bean之前进行的操作

关于在spring  容器初始化 bean 和销毁前所做的操作定义方式有三种：
第一种：通过@PostConstruct 和 @PreDestroy 方法 实现初始化和销毁bean之前进行的操作
第二种是：通过 在xml中定义init-method 和  destory-method方法
第三种是：通过bean实现InitializingBean和 DisposableBean接口

下面演示通过  @PostConstruct 和 @PreDestory
1:定义相关的实现类：

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：定义相关的配置文件：

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

其中<context:annotation-config />告诉spring 容器采用注解配置：扫描注解配置
测试类：

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();  
    }  
  
}  

其中也可以通过申明加载org.springframework.context.annotation.CommonAnnotationBeanPostProcessor
类来告诉Spring容器采用的 常用 注解配置的方式：
只需要修改配置文件为：

<?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: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>  

http://blog.csdn.net/topwqp/article/details/8681497

spring加载bean实例化顺序
http://www.cnblogs.com/fanguangdexiaoyuer/p/5886050.html

Bean在实例化的过程中：
Constructor > @PostConstruct > InitializingBean > init-method
http://sexycoding.iteye.com/blog/1046993

Spring中Bean初始化实例【重要】
http://uule.iteye.com/blog/2094609