对象注入 BeanFactory 的操作 BeanFactoryPostProcessor , Spring boot

先看代码

package biz.baijing.processor;import ...@Component
public class BaiJingBeanFactoryPostProcessor implements BeanFactoryPostProcessor {/*-1- beanFactory实例化后，-2- bean创建之前回调 . postProcessBeanFactory ，注册 BeanDefinition*/@Overridepublic void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {// 注册一个 BaiJing 的 BeanDefinitionGenericBeanDefinition genBD = new GenericBeanDefinition();genBD.setBeanClass(BaijingDef.class);// public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFactory implements ConfigurableListableBeanFactory, BeanDefinitionRegistry, Serializable {// 强转DefaultListableBeanFactory defBF = (DefaultListableBeanFactory) beanFactory;// 完成注册defBF.registerBeanDefinition("baijingDef", genBD);}
}

输出结果

package biz.baijing;import ...@SpringBootApplication
public class BizBaiJingApplication
{public static void main( String[] args )ConfigurableApplicationContext run = SpringApplication.run(BizBaiJingApplication.class, args);System.out.println(run.getBean("baijingDef"));}
}

结果

biz.baijing.processor.BaijingDef@794366a5

关于 BaijingDef 

package biz.baijing.processor;// 这个类并没有注解，是「Manual」注入
public class BaijingDef {
}

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