Spring容器生命周期中如前置运行程序和后置运行程序

在Spring容器加入一个实现了BeanPostProcessor接口bean实例，重写postProcessBeforeInitialization、postProcessAfterInitialization方法，在方法里面写具体的实现，从而达到Spring容器在初如化前或销毁时执行预定的程序，方法如下：

1、pop.xml导包

<dependency>
	<groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>5.3.37</version>
</dependency>
<dependency>

2、写一个类实现BeanPostProcessor接口，同时写一个User实体类用于测试
实现类：

package test.spring.model;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;

public class LifeBeanAware implements BeanPostProcessor {

	@Override
	public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
		// TODO Auto-generated method stub
		System.out.println("前置处理");
		return null;
	}

	@Override
	public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
		// TODO Auto-generated method stub
		System.out.println("后置处理");
		return null;
	}

}

User类：

/**
*Description:
*author: ljd
*@date 2024年7月2日 
*@version 1.0 
*/
package test.spring.model;

public class User {
	private int id;
	private String name;

	public int getId() {
		return id;
	}

	public void setId(int id) {
		System.out.println("user赋值");
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public void testPrint() {
		System.out.println("this is test init function");
	}

	@Override
	public String toString() {
		return "User [id=" + id + ", name=" + name + "]";
	}

	public User() {
		super();
	}

}

3、applicationContext.xml配置

<?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.xsd">

	<bean id="user1" init-method="testPrint" destroy-method="testPrint" class="test.spring.model.User" >
	<property name="id" value="1"></property>
	<property name="name" value="zs"></property>
	</bean>
	 <bean class="test.spring.model.LifeBeanAware"></bean>
</beans>

4、测试结果

/**
*Description:
*author: ljd
*@date 2024年7月2日 
*@version 1.0 
*/
package testSpring;

import org.junit.Test;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import test.spring.model.User;

public class TestSpring {
	@Test
	public void testUser() {
		ConfigurableApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
		 User user=ac.getBean(User.class); System.out.println(user);
		ac.close();
		
	}

}