当我想使用dubbo.application.service-discovery.migration

org.springframework.boot.autoconfigure.context.ConfigurationPropertiesAutoConfiguration

org.springframework.boot.autoconfigure.context.LifecycleAutoConfiguration

org.springframework.boot.autoconfigure.context.PropertyPlaceholderAutoConfiguration

org.springframework.boot.autoconfigure.availability.ApplicationAvailabilityAutoConfiguration

org.springframework.boot.autoconfigure.info.ProjectInfoAutoConfiguration

14:26:46.189 ERROR [main] o.springframework.boot.SpringApplication:837 - Application run failed java.lang.NullPointerException: null at org.apache.dubbo.metadata.MetadataInfo.init(MetadataInfo.java:122) at org.apache.dubbo.registry.client.AbstractServiceDiscovery.getRemoteMetadata(AbstractServiceDiscovery.java:164) at org.apache.dubbo.registry.client.event.listener.ServiceInstancesChangedListener.doOnEvent(ServiceInstancesChangedListener.java:155) at org.apache.dubbo.registry.client.event.listener.ServiceInstancesChangedListener.onEvent(ServiceInstancesChangedListener.java:113) at org.apache.dubbo.registry.client.ServiceDiscoveryRegistry.subscribeURLs(ServiceDiscoveryRegistry.java:312) at org.apache.dubbo.registry.client.ServiceDiscoveryRegistry.doSubscribe(ServiceDiscoveryRegistry.java:216) at org.apache.dubbo.registry.client.ServiceDiscoveryRegistry.subscribe(ServiceDiscoveryRegistry.java:184) at org.apache.dubbo.registry.ListenerRegistryWrapper.subscribe(ListenerRegistryWrapper.java:111) at org.apache.dubbo.registry.integration.DynamicDirectory.subscribe(DynamicDirectory.java:180) at org.apache.dubbo.registry.client.ServiceDiscoveryRegistryDirectory.subscribe(ServiceDiscoveryRegistryDirectory.java:107) at org.apache.dubbo.registry.integration.RegistryProtocol.doCreateInvoker(RegistryProtocol.java:569) at org.apache.dubbo.registry.integration.InterfaceCompatibleRegistryProtocol.getServiceDiscoveryInvoker(InterfaceCompatibleRegistryProtocol.java:65) at org.apache.dubbo.registry.client.migration.MigrationInvoker.refreshServiceDiscoveryInvoker(MigrationInvoker.java:428) at org.apache.dubbo.registry.client.migration.MigrationInvoker.migrateToApplicationFirstInvoker(MigrationInvoker.java:244) at org.apache.dubbo.registry.client.migration.MigrationRuleHandler.refreshInvoker(MigrationRuleHandler.java:73) at org.apache.dubbo.registry.client.migration.MigrationRuleHandler.doMigrate(MigrationRuleHandler.java:57) at org.apache.dubbo.registry.client.migration.MigrationRuleListener.onRefer(MigrationRuleListener.java:241) at org.apache.dubbo.registry.integration.RegistryProtocol.interceptInvoker(RegistryProtocol.java:534) at org.apache.dubbo.registry.integration.RegistryProtocol.doRefer(RegistryProtocol.java:504) at org.apache.dubbo.registry.integration.RegistryProtocol.refer(RegistryProtocol.java:486) at org.apache.dubbo.rpc.protocol.ProtocolListenerWrapper.refer(ProtocolListenerWrapper.java:74) at org.apache.dubbo.qos.protocol.QosProtocolWrapper.refer(QosProtocolWrapper.java:83) at org.apache.dubbo.rpc.cluster.filter.ProtocolFilterWrapper.refer(ProtocolFilterWrapper.java:71) at org.apache.dubbo.rpc.protocol.ProtocolSerializationWrapper.refer(ProtocolSerializationWrapper.java:52) at org.apache.dubbo.rpc.Protocol$Adaptive.refer(Protocol$Adaptive.java) at org.apache.dubbo.config.ReferenceConfig.createInvokerForRemote(ReferenceConfig.java:493) at org.apache.dubbo.config.ReferenceConfig.createProxy(ReferenceConfig.java:396) at org.apache.dubbo.config.ReferenceConfig.init(ReferenceConfig.java:279) at org.apache.dubbo.config.ReferenceConfig.get(ReferenceConfig.java:219) at org.apache.dubbo.config.utils.SimpleReferenceCache.get(SimpleReferenceCache.java:110) at org.apache.dubbo.config.deploy.DefaultModuleDeployer.lambda$referServices$6(DefaultModuleDeployer.java:384) at java.util.concurrent.ConcurrentHashMap$ValuesView.forEach(ConcurrentHashMap.java:4707) at org.apache.dubbo.config.deploy.DefaultModuleDeployer.referServices(DefaultModuleDeployer.java:364) at org.apache.dubbo.config.deploy.DefaultModuleDeployer.start(DefaultModuleDeployer.java:151) at org.apache.dubbo.config.spring.context.DubboDeployApplicationListener.onContextRefreshedEvent(DubboDeployApplicationListener.java:111) at org.apache.dubbo.config.spring.context.DubboDeployApplicationListener.onApplicationEvent(DubboDeployApplicationListener.java:100) at org.apache.dubbo.config.spring.context.DubboDeployApplicationListener.onApplicationEvent(DubboDeployApplicationListener.java:45) at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:404) at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:361) at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:898) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:554) at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:143) at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:758) at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:750) at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:405) at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) at org.springframework.boot.SpringApplication.run(SpringApplication.java:1237) at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) at com.clife.family.sports.api.web.ClifeFamilySportsApiWebApplication.main(ClifeFamilySportsApiWebApplication.java:22)

但是，当我把订阅指向为接口唯一FORCE_INTERFACE时，程序能够正常运行并完成预想效果。 这是为什么呢？是应用级还需要其他什么配置嘛？

原提问者GitHub用户Jimy-Guo