通过Spring @PostConstruct 和 @PreDestroy 方法实现初始化和销毁bean之前进

我就是我 2022-03-27 05:59 233阅读 0赞

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][PostConstruct _ _PreDestroy _ _bean]

第二种是：[通过 在xml中定义init-method 和 destory-method方法][_xml_init-method _ destory-method]

第三种是：[ 通过bean实现InitializingBean和 DisposableBean接口][_bean_InitializingBean_ DisposableBean]

下面演示通过 @PostConstruct 和 @PreDestory

1:定义相关的实现类：

**\[java\]** [view plain][] [copy][view plain]

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. \}

2：定义相关的配置文件：

**\[html\]** [view plain][] [copy][view plain]

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.  
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>

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][view plain]

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. \}

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][view plain]

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.  
11. 
12.  
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>

同样可以得到以上测试的输出结果。

[spring]: http://lib.csdn.net/base/javaee
[PostConstruct _ _PreDestroy _ _bean]: http://write.blog.csdn.net/postedit/8681497
[_xml_init-method _ destory-method]: http://blog.csdn.net/topwqp/article/details/8681467
[_bean_InitializingBean_ DisposableBean]: http://blog.csdn.net/topwqp/article/details/8681573
[view plain]: http://blog.csdn.net/topwqp/article/details/8681497#