一 DubboComponentScan查看这个注解包含那些
二 进入DubboComponentScanRegistrar
因为该类实现了ImportBeanDefinitionRegistrar接口,springboot刷新上下文的时候会调用registerBeanDefinitions方法(具体调用https://www.cnblogs.com/kjcc/p/13895903.html)
下面看这个方法做了那些东西:
(1)
public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) { //当前扫描包的路径 Set<String> packagesToScan = getPackagesToScan(importingClassMetadata); registerServiceAnnotationBeanPostProcessor(packagesToScan, registry); // @since 2.7.6 Register the common beans registerCommonBeans(registry); }
(2)进入registerServiceAnnotationBeanPostProcessor(packagesToScan, registry);
private void registerServiceAnnotationBeanPostProcessor(Set<String> packagesToScan, BeanDefinitionRegistry registry) { BeanDefinitionBuilder builder = rootBeanDefinition(ServiceAnnotationBeanPostProcessor.class); builder.addConstructorArgValue(packagesToScan); builder.setRole(BeanDefinition.ROLE_INFRASTRUCTURE); AbstractBeanDefinition beanDefinition = builder.getBeanDefinition(); BeanDefinitionReaderUtils.registerWithGeneratedName(beanDefinition, registry); }
这个方法主要作用就是ServiceAnnotationBeanPostProcessor把这个类交给spring容器,首先获取到bean的定义,然后调用工具类创建实例交给容器
(3) registerCommonBeans(registry);主要作用就是把dubbo一些定义的后置处理器和监听器交给spring容器
registerInfrastructureBean(registry, ReferenceAnnotationBeanPostProcessor.BEAN_NAME, ReferenceAnnotationBeanPostProcessor.class); // Since 2.7.4 [Feature] https://github.com/apache/dubbo/issues/5093 registerInfrastructureBean(registry, DubboConfigAliasPostProcessor.BEAN_NAME, DubboConfigAliasPostProcessor.class); // Since 2.7.5 Register DubboLifecycleComponentApplicationListener as an infrastructure Bean registerInfrastructureBean(registry, DubboLifecycleComponentApplicationListener.BEAN_NAME, DubboLifecycleComponentApplicationListener.class); // Since 2.7.4 Register DubboBootstrapApplicationListener as an infrastructure Bean registerInfrastructureBean(registry, DubboBootstrapApplicationListener.BEAN_NAME, DubboBootstrapApplicationListener.class); // Since 2.7.6 Register DubboConfigDefaultPropertyValueBeanPostProcessor as an infrastructure Bean registerInfrastructureBean(registry, DubboConfigDefaultPropertyValueBeanPostProcessor.BEAN_NAME, DubboConfigDefaultPropertyValueBeanPostProcessor.class);
原文：https://www.cnblogs.com/kjcc/p/14550297.html