SpringBoot中如何使用ImportBeanDefinitionRegistrar实现自定义RPC框架？

一、自定义RPC框架使用场景示例 1. 需求场景：服务注册与发现的自动配置 入口注解设计： @Target(ElementType.TYPE) @Retention(RetentionPolicy.RUNTIME) @Documented @Import(RpcComponentRegistrar.class) public @interface EnableRpc { // 扫描的包路径 String[] basePackages() default {}; // 注册中心类型 RegistryType registry() default RegistryType.ZOOKEEPER; // 协议类型 ProtocolType protocol() default ProtocolType.HTTP; } 2. RpcComponentRegistrar的多阶段注册 public class RpcComponentRegistrar implements ImportBeanDefinitionRegistrar, EnvironmentAware { private Environment environment; @Override public void setEnvironment(Environment environment) { this.environment = environment; } @Override public void registerBeanDefinitions( AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry ) { // 阶段1：解析配置 AnnotationAttributes attributes = AnnotationAttributes.fromMap( importingClassMetadata.getAnnotationAttributes(EnableRpc.class.getName())); // 阶段2：根据配置动态注册核心组件 registerRegistryCenter(registry, attributes); registerProtocolProcessor(registry, attributes); registerLoadBalancer(registry, attributes); // 阶段3：扫描并注册服务提供者和消费者 scanAndRegisterServices(registry, attributes); } private void registerRegistryCenter( BeanDefinitionRegistry registry, AnnotationAttributes attributes ) { RegistryType type = attributes.getEnum("registry"); RootBeanDefinition beanDefinition = new RootBeanDefinition(); beanDefinition.setBeanClassName(getRegistryClassByType(type)); // 从Environment读取配置（如zookeeper地址） beanDefinition.getPropertyValues().add("address", environment.getProperty("rpc.registry.address")); registry.registerBeanDefinition("rpcRegistryCenter", beanDefinition); } private void scanAndRegisterServices( BeanDefinitionR