Spring中bean初始化与销毁的三种方式

一、生命周期

1. 定义
2. 初始化
3. 使用
4. 销毁

二、初始化与销毁的三种方式

1.  实现org.springframework.beans.factory.InitializingBean接口，覆盖afterPropertiesSet方法

首先beans.xml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"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

   <bean id="zhangSan3" class="com.kjgym.service.ZhangSan2"></bean>
</beans>

然后bean类

package com.kjgym.service;

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

public class ZhangSan2 implements InitializingBean,DisposableBean{

	@Override
	public void destroy() throws Exception {
		System.out.println("destroy");
	}

	@Override
	public void afterPropertiesSet() throws Exception {
		System.out.println("afterPropertiesSet");
	}
}

测试类 

package com.kjgym.test;

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

public class Test3 {

	public static void main(String[] args) {
		ApplicationContext ac = 
				new ClassPathXmlApplicationContext("beans.xml");
		ac.getBean("zhangSan3");
		((AbstractApplicationContext) ac).close();
		
	}
}

 2.  配置init-method与destroy-method

首先beans.xml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"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">
    
    
   <!-- 第一种初始化和销毁方法 -->
   <bean id="zhangSan2" class="com.kjgym.service.ZhangSan2" init-method="start" destroy-method="stop"></bean>
 

   
 </beans>

对应beans类

package com.kjgym.service;

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

public class ZhangSan2 {

	public void start(){
		System.out.println("张三2来了");
	}
	public void stop(){
		System.out.println("张三2走了");
	}
}

测试类

package com.kjgym.test;

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

public class Test3 {

	public static void main(String[] args) {
		ApplicationContext ac = 
				new ClassPathXmlApplicationContext("beans.xml");
		ac.getBean("zhangSan2");
		((AbstractApplicationContext) ac).close();
		
	}
}

第三种是直接在配置文件里写入，如下图。再写方法，与第二种差不多。