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：

[java] view plain copy

print?

1. package com.myapp.core.annotation.init;  
2.   
3. import javax.annotation.PostConstruct;  
4. import javax.annotation.PreDestroy;  
5.   
6. public class PersonService {  
7.     
8.     private String  message;  
9.   
10.     public String getMessage() {  
11.         return message;  
12.     }  
13.   
14.     public void setMessage(String message) {  
15.         this.message = message;  
16.     }  
17.       
18.     @PostConstruct  
19.     public void  init(){  
20.         System.out.println(”I’m  init  method  using  @PostConstrut….”+message);  
21.     }  
22.       
23.     @PreDestroy  
24.     public void  dostory(){  
25.         System.out.println(”I’m  destory method  using  @PreDestroy…..”+message);  
26.     }  
27.       
28. }  

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：

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print?

1. <?xml version=“1.0” encoding=“UTF-8”?>  
2. <beans xmlns=“http://www.springframework.org/schema/beans”  
3. xmlns:xsi=“http://www.w3.org/2001/XMLSchema-instance”  
4. xmlns:context=“http://www.springframework.org/schema/context”  
5. xsi:schemaLocation=”http://www.springframework.org/schema/beans  
6. http://www.springframework.org/schema/beans/spring-beans-3.1.xsd  
7. http://www.springframework.org/schema/context  
8. http://www.springframework.org/schema/context/spring-context-3.1.xsd”>  
9.   
10. <!– <context:component-scan  base-package=”com.myapp.core.jsr330”/> –>  
11.   
12. <context:annotation-config />  
13.   
14. <bean id=“personService” class=“com.myapp.core.annotation.init.PersonService”>  
15.   <property name=“message” value=“123”></property>  
16. </bean>  
17.   
18. </beans>  

<?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/beanshttp://www.springframework.org/schema/beans/spring-beans-3.1.xsdhttp://www.springframework.org/schema/contexthttp://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<context:annotation-config />告诉spring 容器采用注解配置：扫描注解配置；

测试类：

[java] view plain copy

print?

1. package com.myapp.core.annotation.init;  
2.   
3. import org.springframework.context.ApplicationContext;  
4. import org.springframework.context.support.ClassPathXmlApplicationContext;  
5.   
6. public class MainTest {  
7.       
8.     public static void main(String[] args) {  
9.           
10.         ApplicationContext  context = new ClassPathXmlApplicationContext(“resource/annotation.xml”);  
11.           
12.         PersonService   personService  =  (PersonService)context.getBean(”personService”);  
13.           
14.         personService.dostory();  
15.     }  
16.   
17. }  

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();    }}

测试结果：

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

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：

[html] view plain copy

print?

1. <?xml version=“1.0” encoding=“UTF-8”?>  
2. <beans xmlns=“http://www.springframework.org/schema/beans”  
3. xmlns:xsi=“http://www.w3.org/2001/XMLSchema-instance”  
4. xmlns:context=“http://www.springframework.org/schema/context”  
5. xsi:schemaLocation=”http://www.springframework.org/schema/beans  
6. http://www.springframework.org/schema/beans/spring-beans-3.1.xsd  
7. http://www.springframework.org/schema/context  
8. http://www.springframework.org/schema/context/spring-context-3.1.xsd”>  
9.   
10. <!– <context:component-scan  base-package=”com.myapp.core.jsr330”/> –>  
11.   
12. <!– <context:annotation-config /> –>  
13.   
14.   
15. <bean class=“org.springframework.context.annotation.CommonAnnotationBeanPostProcessor” />  
16. <bean id=“personService” class=“com.myapp.core.annotation.init.PersonService”>  
17.           <property name=“message” value=“123”></property>  
18. </bean>  
19.   
20.   
21.   
22. </beans>  

<?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/beanshttp://www.springframework.org/schema/beans/spring-beans-3.1.xsdhttp://www.springframework.org/schema/contexthttp://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>

同样可以得到以上测试的输出结果。