Spring之Bean的生命周期过程中调用的方法

1。这个部分除了6,9都在这了

java 复制代码

package com.example.springbootdemo3.lifebeean;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.*;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;

/**
 * description
 *
 * @author PC 2025/02/27 20:26
 */
@Component
public class MyBeanLife implements BeanNameAware, BeanFactoryAware, ApplicationContextAware, InitializingBean, DisposableBean {


    private String name;

    // 构造函数，当Bean被实例化时调用
    public MyBeanLife() {
        System.out.println("1.调用了Bean的构造函数");
    }

    @Value("name")
    public void setName(String name) {
        this.name = name;
        System.out.println("2.调用了Bean的set方法(属性的依赖注入)");
    }

    @Override
    public void setBeanName(String s) {
        System.out.println("3.调用了BeanNameAware的setBeanName方法,beanName:" + s);
    }

    @Override
    public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
        System.out.println("4.调用了BeanFactoryAware的setBeanFactory方法,beanFactory:" + beanFactory.toString());
    }

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        System.out.println("5.调用了ApplicationContextAware的setApplicationContext方法,applicationContext:" + applicationContext.toString());
    }

    @PostConstruct
    public void postConstruct() {
        System.out.println("7.调用了@PostConstruct注解的方法");
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        System.out.println("8.调用了InitializingBean的afterPropertiesSet方法");
    }

    @PreDestroy
    public void preDestroy() {
        System.out.println("10.调用了@PreDestroy注解的方法");
    }

    @Override
    public void destroy() throws Exception {
        System.out.println("11.调用了DisposableBean的destroy方法");
    }
}

2. 6和9部分

BeanPostProcessor的两个方法是所有Bean都会调用，除了实现这个接口的Bean，所以为了方便加了判断

java 复制代码

package com.example.springbootdemo3.lifebeean;

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

/**
 * description
 *
 * @author PC 2025/02/27 21:00
 */
@Component
public class MyBeanLife2 implements BeanPostProcessor {
    @Override
    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
        if (!beanName.equals("myBeanLife")) {
            return bean;
        }
        System.out.println("6.调用了BeanPostProcessor的postProcessBeforeInitialization方法,beanName:" + beanName);
        return bean;
    }

    @Override
    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
        if (!beanName.equals("myBeanLife")) {
            return bean;
        }
        System.out.println("9.调用了BeanPostProcessor的postProcessAfterInitialization方法,beanName:" + beanName);
        return bean;
    }
}