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: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=""></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();
} }
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:
<?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>
同样可以得到以上测试的输出结果。