Spring扩展点

1 beanPostProcessor 该接口作用是：如果我们需要在Spring容器完成Bean的实例化，配置和其他的初始化后添加一些自己的逻辑处理，我们就可以定义一个或者多个BeanPostProcessor接口的实现。

　　有两个方法

// Bean 实例化之前进行的处理

public Object postProcessBeforeInitialization(Object bean, String beanName)

throws BeansException {

System.out.println("对象" + beanName + "开始实例化");

return bean;

}

// Bean 实例化之后进行的处理

public Object postProcessAfterInitialization(Object bean, String beanName)

throws BeansException {

System.out.println("对象" + beanName + "实例化完成");

return bean;

}

2 容器创建相关回调 BeanFactoryPostProcessor

@Component
public class MyBeanFactoryPostProcessor implements BeanFactoryPostProcessor {

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        System.out.println(beanFactory.containsBean("user"));
        String   []   strs=beanFactory.getSingletonNames();
        for (String string : strs) {
            System.out.println(string);
        }

    }

}

3 如何动态的向容器放入一个bean

@Component
public class MydefinitionRegistery implements BeanDefinitionRegistryPostProcessor {

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory arg0) throws BeansException {
        // TODO Auto-generated method stub

    }


    @Override
    public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) throws BeansException {
        for (int i=0;i<10;i++) {
            BeanDefinitionBuilder  builder = BeanDefinitionBuilder.rootBeanDefinition(User.class);
            builder.addPropertyValue("name", "HZZ"+i);
            builder.addPropertyValue("age", 15+i);
            builder.addPropertyValue("time", new Date());
            registry.registerBeanDefinition("user——def"+i,builder.getBeanDefinition());
        }

    }

}

Spring扩展点

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