spring的bean工厂后置处理器

spring的bean工厂后置处理器的回调时期是在bean实例化之前，把我们的spring配置文件解析完成之后，把bean工厂初始化之后，调用bean工厂后置处理器之后才调用bean的创建过程。我们可以对bean的定义进行修改。

spring5.xml

<?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:p="http://www.springframework.org/schema/p"
       xmlns:context="http://www.springframework.org/schema/context" xmlns:c="http://www.springframework.org/schema/c"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">

      <bean id="user" class="com.video.spring.User"></bean>
      <bean id="b" class="com.video.spring.MyBeanFactoryPostProcessor"></bean>
 
</beans>

import lombok.Data;

@Data
public class User {

    private int id;
    private String name;

    public User() {
        System.out.println("user 构造方法");
    }

    public void init1() {
        System.out.println("User init1");
    }

    public void destory1() {
        System.out.println("User destory1");
    }
}

MyBeanFactoryPostProcessor

BeanFactoryPostProcessor ：实现BeanFactoryPostProcessor ， bean工厂后置处理器
Ordered ： 实现Ordered ，bean工厂后置处理器执行顺序，数字越小，越先执行

public class MyBeanFactoryPostProcessor implements BeanFactoryPostProcessor, Ordered {

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        System.out.println("MyBeanFactoryPostProcessor 101010");

        AbstractBeanDefinition abstractBeanDefinition = (AbstractBeanDefinition) beanFactory.getBeanDefinition("user");
        //设置user创建之前，执行init方法
        abstractBeanDefinition.setInitMethodName("init1");
        abstractBeanDefinition.setDestroyMethodName("destory1");
        //给user属性赋值
        MutablePropertyValues mutablePropertyValues = abstractBeanDefinition.getPropertyValues();
        //给user的name属性赋值为beanfactory modify name
        mutablePropertyValues.addPropertyValue("name", "beanfactory modify name");


    }

    @Override
    public int getOrder() {
        return 10;
    }
}