sync & commit in greenwich

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/autoconfigure/DubboLoadBalancedRestTemplateAutoConfiguration.java

@@ -13,30 +13,14 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.cloud.dubbo.autoconfigure;
 
-import java.util.*;
-
-import org.springframework.beans.factory.BeanClassLoaderAware;
-import org.springframework.beans.factory.SmartInitializingSingleton;
-import org.springframework.beans.factory.annotation.AnnotatedBeanDefinition;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.config.BeanDefinition;
-import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
-import org.springframework.boot.autoconfigure.AutoConfigureAfter;
-import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
-import org.springframework.boot.context.event.ApplicationStartedEvent;
-import org.springframework.cloud.client.loadbalancer.LoadBalanced;
-import org.springframework.cloud.client.loadbalancer.LoadBalancerInterceptor;
-import org.springframework.cloud.client.loadbalancer.RestTemplateCustomizer;
-import org.springframework.cloud.client.loadbalancer.RetryLoadBalancerInterceptor;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.context.event.EventListener;
-import org.springframework.core.env.Environment;
-import org.springframework.core.type.MethodMetadata;
-import org.springframework.http.client.ClientHttpRequestInterceptor;
-import org.springframework.util.CollectionUtils;
-import org.springframework.web.client.RestTemplate;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
 
 import com.alibaba.cloud.dubbo.annotation.DubboTransported;
 import com.alibaba.cloud.dubbo.client.loadbalancer.DubboMetadataInitializerInterceptor;
@@ -46,9 +30,33 @@ import com.alibaba.cloud.dubbo.metadata.resolver.DubboTransportedAttributesResol
 import com.alibaba.cloud.dubbo.service.DubboGenericServiceExecutionContextFactory;
 import com.alibaba.cloud.dubbo.service.DubboGenericServiceFactory;
 
+import org.springframework.beans.factory.BeanClassLoaderAware;
+import org.springframework.beans.factory.SmartInitializingSingleton;
+import org.springframework.beans.factory.annotation.AnnotatedBeanDefinition;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.config.BeanDefinition;
+import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
+import org.springframework.boot.autoconfigure.AutoConfigureAfter;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.cloud.client.loadbalancer.LoadBalanced;
+import org.springframework.cloud.client.loadbalancer.LoadBalancerInterceptor;
+import org.springframework.cloud.client.loadbalancer.RestTemplateCustomizer;
+import org.springframework.cloud.client.loadbalancer.RetryLoadBalancerInterceptor;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.event.ContextRefreshedEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.core.env.Environment;
+import org.springframework.core.type.MethodMetadata;
+import org.springframework.http.client.ClientHttpRequestInterceptor;
+import org.springframework.lang.Nullable;
+import org.springframework.util.CollectionUtils;
+import org.springframework.web.client.RestTemplate;
+
 /**
  * Dubbo Auto-{@link Configuration} for {@link LoadBalanced @LoadBalanced}
- * {@link RestTemplate}
+ * {@link RestTemplate}.
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  */
@@ -56,8 +64,8 @@ import com.alibaba.cloud.dubbo.service.DubboGenericServiceFactory;
 @ConditionalOnClass(name = { "org.springframework.web.client.RestTemplate" })
 @AutoConfigureAfter(name = {
 		"org.springframework.cloud.client.loadbalancer.LoadBalancerAutoConfiguration" })
-public class DubboLoadBalancedRestTemplateAutoConfiguration
-		implements BeanClassLoaderAware, SmartInitializingSingleton {
+public class DubboLoadBalancedRestTemplateAutoConfiguration implements
+		BeanClassLoaderAware, ApplicationContextAware, SmartInitializingSingleton {
 
 	private static final Class<DubboTransported> DUBBO_TRANSPORTED_CLASS = DubboTransported.class;
 
@@ -89,19 +97,21 @@ public class DubboLoadBalancedRestTemplateAutoConfiguration
 	@Autowired(required = false)
 	private Map<String, RestTemplate> restTemplates = Collections.emptyMap();
 
+	@Nullable
+	private ApplicationContext applicationContext;
+
 	private ClassLoader classLoader;
 
 	/**
 	 * The {@link ClientHttpRequestInterceptor} bean that may be
-	 * {@link LoadBalancerInterceptor} or {@link RetryLoadBalancerInterceptor}
+	 * {@link LoadBalancerInterceptor} or {@link RetryLoadBalancerInterceptor}.
 	 */
 	private ClientHttpRequestInterceptor loadBalancerInterceptorBean;
 
 	@Override
 	public void afterSingletonsInstantiated() {
 		loadBalancerInterceptorBean = retryLoadBalancerInterceptor != null
-				? retryLoadBalancerInterceptor
-				: loadBalancerInterceptor;
+				? retryLoadBalancerInterceptor : loadBalancerInterceptor;
 	}
 
 	/**
@@ -109,28 +119,31 @@ public class DubboLoadBalancedRestTemplateAutoConfiguration
 	 * {@link LoadBalanced @LoadBalanced} and {@link LoadBalanced @LoadBalanced} when
 	 * Spring Boot application started (after the callback of
 	 * {@link SmartInitializingSingleton} beans or
-	 * {@link RestTemplateCustomizer#customize(RestTemplate) customization})
+	 * {@link RestTemplateCustomizer#customize(RestTemplate) customization}).
+	 * @param event spring event
 	 */
-	@EventListener(ApplicationStartedEvent.class)
-	public void adaptRestTemplates() {
+	@EventListener(ContextRefreshedEvent.class)
+	public void adaptRestTemplates(ContextRefreshedEvent event) {
 
-		DubboTransportedAttributesResolver attributesResolver = new DubboTransportedAttributesResolver(
-				environment);
+		if (event.getApplicationContext() == this.applicationContext) {
 
-		for (Map.Entry<String, RestTemplate> entry : restTemplates.entrySet()) {
-			String beanName = entry.getKey();
-			Map<String, Object> dubboTranslatedAttributes = getDubboTranslatedAttributes(
-					beanName, attributesResolver);
-			if (!CollectionUtils.isEmpty(dubboTranslatedAttributes)) {
-				adaptRestTemplate(entry.getValue(), dubboTranslatedAttributes);
+			DubboTransportedAttributesResolver attributesResolver = new DubboTransportedAttributesResolver(
+					environment);
+
+			for (Map.Entry<String, RestTemplate> entry : restTemplates.entrySet()) {
+				String beanName = entry.getKey();
+				Map<String, Object> dubboTranslatedAttributes = getDubboTranslatedAttributes(
+						beanName, attributesResolver);
+				if (!CollectionUtils.isEmpty(dubboTranslatedAttributes)) {
+					adaptRestTemplate(entry.getValue(), dubboTranslatedAttributes);
+				}
 			}
 		}
 	}
 
 	/**
 	 * Gets the annotation attributes {@link RestTemplate} bean being annotated
-	 * {@link DubboTransported @DubboTransported}
-	 *
+	 * {@link DubboTransported @DubboTransported}.
 	 * @param beanName the bean name of {@link LoadBalanced @LoadBalanced}
 	 * {@link RestTemplate}
 	 * @param attributesResolver {@link DubboTransportedAttributesResolver}
@@ -144,10 +157,10 @@ public class DubboLoadBalancedRestTemplateAutoConfiguration
 			AnnotatedBeanDefinition annotatedBeanDefinition = (AnnotatedBeanDefinition) beanDefinition;
 			MethodMetadata factoryMethodMetadata = annotatedBeanDefinition
 					.getFactoryMethodMetadata();
-			attributes = factoryMethodMetadata != null
-					? Optional.ofNullable(factoryMethodMetadata
-							.getAnnotationAttributes(DUBBO_TRANSPORTED_CLASS_NAME)).orElse(attributes)
-					: Collections.emptyMap();
+			attributes = factoryMethodMetadata != null ? Optional
+					.ofNullable(factoryMethodMetadata
+							.getAnnotationAttributes(DUBBO_TRANSPORTED_CLASS_NAME))
+					.orElse(attributes) : Collections.emptyMap();
 		}
 		return attributesResolver.resolve(attributes);
 	}
@@ -155,7 +168,6 @@ public class DubboLoadBalancedRestTemplateAutoConfiguration
 	/**
 	 * Adapt the instance of {@link DubboTransporterInterceptor} to the
 	 * {@link LoadBalancerInterceptor} Bean.
-	 *
 	 * @param restTemplate {@link LoadBalanced @LoadBalanced} {@link RestTemplate} Bean
 	 * @param dubboTranslatedAttributes the annotation dubboTranslatedAttributes
 	 * {@link RestTemplate} bean being annotated
@@ -188,4 +200,9 @@ public class DubboLoadBalancedRestTemplateAutoConfiguration
 		this.classLoader = classLoader;
 	}
 
+	@Override
+	public void setApplicationContext(ApplicationContext applicationContext) {
+		this.applicationContext = applicationContext;
+	}
+
 }

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/autoconfigure/DubboMetadataAutoConfiguration.java

@@ -16,23 +16,12 @@
 package com.alibaba.cloud.dubbo.autoconfigure;
 
 import java.util.Collection;
+import java.util.Optional;
 import java.util.function.Supplier;
 
-import org.apache.dubbo.config.ProtocolConfig;
-import org.apache.dubbo.config.spring.ServiceBean;
-import org.apache.dubbo.config.spring.context.event.ServiceBeanExportedEvent;
-import org.springframework.beans.factory.ObjectProvider;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
-import org.springframework.boot.context.event.ApplicationFailedEvent;
-import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.context.annotation.Import;
-import org.springframework.context.event.ContextClosedEvent;
-import org.springframework.context.event.EventListener;
-
 import com.alibaba.cloud.dubbo.metadata.DubboProtocolConfigSupplier;
 import com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository;
+import com.alibaba.cloud.dubbo.metadata.repository.MetadataServiceInstanceSelector;
 import com.alibaba.cloud.dubbo.metadata.resolver.DubboServiceBeanMetadataResolver;
 import com.alibaba.cloud.dubbo.metadata.resolver.MetadataResolver;
 import com.alibaba.cloud.dubbo.service.DubboGenericServiceFactory;
@@ -42,6 +31,20 @@ import com.alibaba.cloud.dubbo.service.IntrospectiveDubboMetadataService;
 import com.alibaba.cloud.dubbo.util.JSONUtils;
 
 import feign.Contract;
+import org.apache.dubbo.config.ProtocolConfig;
+import org.apache.dubbo.config.spring.ServiceBean;
+import org.apache.dubbo.config.spring.context.event.ServiceBeanExportedEvent;
+
+import org.springframework.beans.factory.ObjectProvider;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.context.event.ApplicationFailedEvent;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+import org.springframework.context.event.ContextClosedEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.util.CollectionUtils;
 
 /**
  * Spring Boot Auto-Configuration class for Dubbo Metadata
@@ -68,6 +71,14 @@ public class DubboMetadataAutoConfiguration {
 		return new DubboServiceBeanMetadataResolver(contract);
 	}
 
+	@Bean
+	@ConditionalOnMissingBean
+	public MetadataServiceInstanceSelector metadataServiceInstanceSelector() {
+		return serviceInstances -> CollectionUtils.isEmpty(serviceInstances)
+				? Optional.empty()
+				: serviceInstances.stream().findAny();
+	}
+
 	@Bean
 	public Supplier<ProtocolConfig> dubboProtocolConfigSupplier(
 			ObjectProvider<Collection<ProtocolConfig>> protocols) {

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/autoconfigure/DubboOpenFeignAutoConfiguration.java

@@ -39,6 +39,9 @@ import com.alibaba.cloud.dubbo.service.DubboGenericServiceFactory;
 @Configuration
 public class DubboOpenFeignAutoConfiguration {
 
+	/**
+	 * OpenFeign Targeter class name.
+	 */
 	public static final String TARGETER_CLASS_NAME = "org.springframework.cloud.openfeign.Targeter";
 
 	@Bean

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/autoconfigure/DubboServiceDiscoveryAutoConfiguration.java

@@ -105,10 +105,19 @@ import com.netflix.discovery.shared.Applications;
 				DubboServiceRegistrationAutoConfiguration.class })
 public class DubboServiceDiscoveryAutoConfiguration {
 
+	/**
+	 * ZookeeperDiscoveryAutoConfiguration.
+	 */
 	public static final String ZOOKEEPER_DISCOVERY_AUTO_CONFIGURATION_CLASS_NAME = "org.springframework.cloud.zookeeper.discovery.ZookeeperDiscoveryAutoConfiguration";
 
+	/**
+	 * ConsulDiscoveryClientConfiguration.
+	 */
 	public static final String CONSUL_DISCOVERY_AUTO_CONFIGURATION_CLASS_NAME = "org.springframework.cloud.consul.discovery.ConsulDiscoveryClientConfiguration";
 
+	/**
+	 * NacosDiscoveryAutoConfiguration.
+	 */
 	public static final String NACOS_DISCOVERY_AUTO_CONFIGURATION_CLASS_NAME = "com.alibaba.cloud.nacos.NacosDiscoveryAutoConfiguration";
 
 	private final DubboServiceMetadataRepository dubboServiceMetadataRepository;

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/metadata/RequestMetadata.java

@@ -73,8 +73,7 @@ public class RequestMetadata {
 	}
 
 	/**
-	 * Get the best matched {@link RequestMetadata} via specified {@link RequestMetadata}
-	 *
+	 * Get the best matched {@link RequestMetadata} via specified {@link RequestMetadata}.
 	 * @param requestMetadataMap the source of {@link NavigableMap}
 	 * @param requestMetadata the match object
 	 * @return if not matched, return <code>null</code>

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/metadata/RestMethodMetadata.java

@@ -27,7 +27,7 @@ import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonProperty;
 
 /**
- * Method Request Metadata
+ * Method Request Metadata.
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  */

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/metadata/ServiceRestMetadata.java

@@ -21,7 +21,7 @@ import java.util.Set;
 import com.fasterxml.jackson.annotation.JsonInclude;
 
 /**
- * Service Rest Metadata
+ * Service Rest Metadata.
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  * @see RestMethodMetadata

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/metadata/repository/DubboServiceMetadataRepository.java

@@ -88,13 +88,13 @@ public class DubboServiceMetadataRepository
 
 	/**
 	 * The {@link URL URLs} property name of {@link DubboMetadataService} :
-	 * "dubbo.metadata-service.urls"
+	 * "dubbo.metadata-service.urls".
 	 */
 	public static final String DUBBO_METADATA_SERVICE_URLS_PROPERTY_NAME = DUBBO_METADATA_SERVICE_PREFIX
 			+ "urls";
 
 	/**
-	 * The {@link String#format(String, Object...) pattern} of dubbo protocols port
+	 * The {@link String#format(String, Object...) pattern} of dubbo protocols port.
 	 */
 	public static final String DUBBO_PROTOCOLS_PORT_PROPERTY_NAME_PATTERN = "dubbo.protocols.%s.port";
 
@@ -103,17 +103,19 @@ public class DubboServiceMetadataRepository
 	private final ObjectMapper objectMapper = new ObjectMapper();
 
 	/**
-	 * Monitor object for synchronization
+	 * Monitor object for synchronization.
 	 */
 	private final Object monitor = new Object();
+
 	/**
-	 * A {@link Set} of service names that had been initialized
+	 * A {@link Set} of service names that had been initialized.
 	 */
 	private final Set<String> initializedServices = new LinkedHashSet<>();
+
 	/**
 	 * All exported {@link URL urls} {@link Map} whose key is the return value of
 	 * {@link URL#getServiceKey()} method and value is the {@link List} of {@link URL
-	 * URLs}
+	 * URLs}.
 	 */
 	private final MultiValueMap<String, URL> allExportedURLs = new LinkedMultiValueMap<>();
 
@@ -122,7 +124,7 @@ public class DubboServiceMetadataRepository
 	/**
 	 * The subscribed {@link URL urls} {@link Map} of {@link DubboMetadataService}, whose
 	 * key is the return value of {@link URL#getServiceKey()} method and value is the
-	 * {@link List} of {@link URL URLs}
+	 * {@link List} of {@link URL URLs}.
 	 */
 	private final MultiValueMap<String, URL> subscribedDubboMetadataServiceURLs = new LinkedMultiValueMap<>();
 
@@ -145,8 +147,10 @@ public class DubboServiceMetadataRepository
 	// =================================== REST Metadata
 	// ================================== //
 	private volatile Set<String> subscribedServices = emptySet();
+
 	/**
-	 * Key is application name Value is Map<RequestMetadata, DubboRestServiceMetadata>
+	 * Key is application name Value is Map&lt;RequestMetadata,
+	 * DubboRestServiceMetadata&gt;.
 	 */
 	private Map<String, Map<RequestMetadataMatcher, DubboRestServiceMetadata>> dubboRestServiceMetadataRepository = newHashMap();
 
@@ -165,6 +169,9 @@ public class DubboServiceMetadataRepository
 	@Autowired
 	private DiscoveryClient discoveryClient;
 
+	@Autowired
+	private MetadataServiceInstanceSelector metadataServiceInstanceSelector;
+
 	@Autowired
 	private JSONUtils jsonUtils;
 
@@ -199,9 +206,8 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Initialize {@link #subscribedServices the subscribed services}
-	 *
-	 * @return
+	 * Initialize {@link #subscribedServices the subscribed services}.
+	 * @return stream of subscribed services
 	 */
 	@PostConstruct
 	public Stream<String> initSubscribedServices() {
@@ -253,7 +259,7 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Initialize the metadata
+	 * Initialize the metadata.
 	 */
 	private void initializeMetadata() {
 		doGetSubscribedServices().forEach(this::initializeMetadata);
@@ -263,7 +269,8 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Initialize the metadata of Dubbo Services
+	 * Initialize the metadata of Dubbo Services.
+	 * @param serviceName service of name
 	 */
 	public void initializeMetadata(String serviceName) {
 		synchronized (monitor) {
@@ -281,9 +288,7 @@ public class DubboServiceMetadataRepository
 							serviceName);
 				}
 
-				// Keep the order in following invocations
 				initSubscribedDubboMetadataService(serviceName);
-				initDubboRestServiceMetadataRepository(serviceName);
 				// mark this service name having been initialized
 				initializedServices.add(serviceName);
 			}
@@ -291,7 +296,7 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Remove the metadata of Dubbo Services if no there is no service instance
+	 * Remove the metadata of Dubbo Services if no there is no service instance.
 	 * @param serviceName the service name
 	 */
 	public void removeInitializedService(String serviceName) {
@@ -301,8 +306,7 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Get the metadata {@link Map} of {@link DubboMetadataService}
-	 *
+	 * Get the metadata {@link Map} of {@link DubboMetadataService}.
 	 * @return non-null read-only {@link Map}
 	 */
 	public Map<String, String> getDubboMetadataServiceMetadata() {
@@ -342,8 +346,7 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Get the property name of Dubbo Protocol
-	 *
+	 * Get the property name of Dubbo Protocol.
 	 * @param protocol Dubbo Protocol
 	 * @return non-null
 	 */
@@ -352,8 +355,7 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Publish the {@link Set} of {@link ServiceRestMetadata}
-	 *
+	 * Publish the {@link Set} of {@link ServiceRestMetadata}.
 	 * @param serviceRestMetadataSet the {@link Set} of {@link ServiceRestMetadata}
 	 */
 	public void publishServiceRestMetadata(
@@ -366,8 +368,7 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Get the {@link Set} of {@link ServiceRestMetadata}
-	 *
+	 * Get the {@link Set} of {@link ServiceRestMetadata}.
 	 * @return non-null read-only {@link Set}
 	 */
 	public Set<ServiceRestMetadata> getServiceRestMetadata() {
@@ -396,10 +397,9 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * The specified service is subscribe or not
-	 *
+	 * The specified service is subscribe or not.
 	 * @param serviceName the service name
-	 * @return
+	 * @return subscribe or not
 	 */
 	public boolean isSubscribedService(String serviceName) {
 		return doGetSubscribedServices().contains(serviceName);
@@ -431,7 +431,6 @@ public class DubboServiceMetadataRepository
 
 	/**
 	 * Get all exported {@link URL urls}.
-	 *
 	 * @return non-null read-only
 	 */
 	public Map<String, List<URL>> getAllExportedUrls() {
@@ -439,8 +438,7 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Get all exported {@link URL#getServiceKey() service keys}
-	 *
+	 * Get all exported {@link URL#getServiceKey() service keys}.
 	 * @return non-null read-only
 	 */
 	public Set<String> getAllServiceKeys() {
@@ -449,8 +447,7 @@ public class DubboServiceMetadataRepository
 
 	/**
 	 * Get the {@link URL urls} that {@link DubboMetadataService} exported by the
-	 * specified {@link ServiceInstance}
-	 *
+	 * specified {@link ServiceInstance}.
 	 * @param serviceInstance {@link ServiceInstance}
 	 * @return the mutable {@link URL urls}
 	 */
@@ -475,8 +472,7 @@ public class DubboServiceMetadataRepository
 	}
 
 	/**
-	 * Initialize the specified service's {@link ServiceRestMetadata}
-	 *
+	 * Initialize the specified service's {@link ServiceRestMetadata}.
 	 * @param serviceName the service name
 	 */
 	protected void initDubboRestServiceMetadataRepository(String serviceName) {
@@ -521,8 +517,7 @@ public class DubboServiceMetadataRepository
 
 	/**
 	 * Get a {@link DubboRestServiceMetadata} by the specified service name if
-	 * {@link RequestMetadata} matched
-	 *
+	 * {@link RequestMetadata} matched.
 	 * @param serviceName service name
 	 * @param requestMetadata {@link RequestMetadata} to be matched
 	 * @return {@link DubboRestServiceMetadata} if matched, or <code>null</code>
@@ -618,7 +613,7 @@ public class DubboServiceMetadataRepository
 	}
 
 	protected void initSubscribedDubboMetadataService(String serviceName) {
-		discoveryClient.getInstances(serviceName).stream().findAny()
+		metadataServiceInstanceSelector.choose(discoveryClient.getInstances(serviceName))
 				.map(this::getDubboMetadataServiceURLs)
 				.ifPresent(dubboMetadataServiceURLs -> {
 					dubboMetadataServiceURLs.forEach(dubboMetadataServiceURL -> {
@@ -634,6 +629,7 @@ public class DubboServiceMetadataRepository
 						}
 					});
 				});
+		initDubboRestServiceMetadataRepository(serviceName);
 	}
 
 	private void initSubscribedDubboMetadataServiceURL(URL dubboMetadataServiceURL) {
@@ -649,8 +645,9 @@ public class DubboServiceMetadataRepository
 		dubboMetadataConfigServiceProxy.initProxy(serviceName, version);
 	}
 
-	public void removeServiceMetadata(String serviceName) {
+	public void removeMetadata(String serviceName) {
 		dubboRestServiceMetadataRepository.remove(serviceName);
+		subscribedDubboMetadataServiceURLs.remove(serviceName);
 	}
 
 	@Override
@@ -658,4 +655,5 @@ public class DubboServiceMetadataRepository
 			ApplicationEventPublisher applicationEventPublisher) {
 		this.applicationEventPublisher = applicationEventPublisher;
 	}
+
 }

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/metadata/repository/MetadataServiceInstanceSelector.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2013-2018 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.alibaba.cloud.dubbo.metadata.repository;
+
+import java.util.List;
+import java.util.Optional;
+
+import org.springframework.cloud.client.ServiceInstance;
+
+/**
+ * metadata service instance selector.
+ *
+ * @author <a href="mailto:liuxx-u@outlook.com">liuxx</a>
+ */
+public interface MetadataServiceInstanceSelector {
+
+	/**
+	 * choose a service instance to get metadata.
+	 * @param serviceInstances all service instance
+	 * @return the service instance to get metadata
+	 */
+	Optional<ServiceInstance> choose(List<ServiceInstance> serviceInstances);
+
+}

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/metadata/resolver/DubboServiceBeanMetadataResolver.java

@@ -59,7 +59,7 @@ public class DubboServiceBeanMetadataResolver
 	private ClassLoader classLoader;
 
 	/**
-	 * Feign Contracts
+	 * Feign Contracts.
 	 */
 	private Collection<Contract> contracts;
 
@@ -153,9 +153,8 @@ public class DubboServiceBeanMetadataResolver
 	 * Select feign contract methods
 	 * <p>
 	 * extract some code from
-	 * {@link Contract.BaseContract#parseAndValidatateMetadata(java.lang.Class)}
-	 *
-	 * @param targetType
+	 * {@link Contract.BaseContract#parseAndValidatateMetadata(java.lang.Class)}.
+	 * @param targetType class of type
 	 * @return non-null
 	 */
 	private List<Method> selectFeignContractMethods(Class<?> targetType) {

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/metadata/resolver/MetadataResolver.java

@@ -23,25 +23,24 @@ import com.alibaba.cloud.dubbo.metadata.RestMethodMetadata;
 import com.alibaba.cloud.dubbo.metadata.ServiceRestMetadata;
 
 /**
- * The REST metadata resolver
+ * The REST metadata resolver.
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  */
 public interface MetadataResolver {
 
 	/**
-	 * Resolve the {@link ServiceRestMetadata} {@link Set set} from {@link ServiceBean}
-	 *
+	 * Resolve the {@link ServiceRestMetadata} {@link Set set} from {@link ServiceBean}.
 	 * @param serviceBean {@link ServiceBean}
 	 * @return non-null {@link Set}
 	 */
 	Set<ServiceRestMetadata> resolveServiceRestMetadata(ServiceBean serviceBean);
 
 	/**
-	 * Resolve {@link RestMethodMetadata} {@link Set set} from {@link Class target type}
-	 *
+	 * Resolve {@link RestMethodMetadata} {@link Set set} from {@link Class target type}.
 	 * @param targetType {@link Class target type}
 	 * @return non-null {@link Set}
 	 */
 	Set<RestMethodMetadata> resolveMethodRestMetadata(Class<?> targetType);
+
 }

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/registry/AbstractSpringCloudRegistry.java

@@ -13,8 +13,36 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.cloud.dubbo.registry;
 
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Set;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+import com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository;
+import com.alibaba.cloud.dubbo.registry.event.ServiceInstancesChangedEvent;
+import com.alibaba.cloud.dubbo.service.DubboGenericServiceFactory;
+import com.alibaba.cloud.dubbo.service.DubboMetadataService;
+import com.alibaba.cloud.dubbo.service.DubboMetadataServiceProxy;
+import com.alibaba.cloud.dubbo.util.JSONUtils;
+import org.apache.dubbo.common.URL;
+import org.apache.dubbo.registry.NotifyListener;
+import org.apache.dubbo.registry.RegistryFactory;
+import org.apache.dubbo.registry.support.FailbackRegistry;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import org.springframework.cloud.client.ServiceInstance;
+import org.springframework.cloud.client.discovery.DiscoveryClient;
+import org.springframework.context.ApplicationListener;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.util.CollectionUtils;
+
 import static java.util.Arrays.asList;
 import static java.util.Collections.emptyList;
 import static org.apache.dubbo.common.URLBuilder.from;
@@ -27,56 +55,31 @@ import static org.apache.dubbo.common.constants.RegistryConstants.EMPTY_PROTOCOL
 import static org.apache.dubbo.registry.Constants.ADMIN_PROTOCOL;
 import static org.springframework.util.StringUtils.hasText;
 
-import java.util.Collection;
-import java.util.HashSet;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Set;
-import java.util.function.Function;
-import java.util.stream.Collectors;
-
-import org.apache.dubbo.common.URL;
-import org.apache.dubbo.registry.NotifyListener;
-import org.apache.dubbo.registry.RegistryFactory;
-import org.apache.dubbo.registry.support.FailbackRegistry;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.cloud.client.ServiceInstance;
-import org.springframework.cloud.client.discovery.DiscoveryClient;
-import org.springframework.context.ApplicationListener;
-import org.springframework.context.ConfigurableApplicationContext;
-import org.springframework.util.CollectionUtils;
-
-import com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository;
-import com.alibaba.cloud.dubbo.registry.event.ServiceInstancesChangedEvent;
-import com.alibaba.cloud.dubbo.service.DubboMetadataService;
-import com.alibaba.cloud.dubbo.service.DubboMetadataServiceProxy;
-import com.alibaba.cloud.dubbo.util.JSONUtils;
-
 /**
  * Abstract Dubbo {@link RegistryFactory} uses Spring Cloud Service Registration
- * abstraction, whose protocol is "spring-cloud"
+ * abstraction, whose protocol is "spring-cloud".
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  */
 public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 
 	/**
-	 * The parameter name of {@link #servicesLookupInterval}
+	 * The parameter name of {@link #servicesLookupInterval}.
 	 */
 	public static final String SERVICES_LOOKUP_INTERVAL_PARAM_NAME = "dubbo.services.lookup.interval";
 
 	protected static final String DUBBO_METADATA_SERVICE_CLASS_NAME = DubboMetadataService.class
 			.getName();
+
 	/**
-	 * Caches the IDs of {@link ApplicationListener}
+	 * Caches the IDs of {@link ApplicationListener}.
 	 */
 	private static final Set<String> registerListeners = new HashSet<>();
 
 	protected final Logger logger = LoggerFactory.getLogger(getClass());
 
 	/**
-	 * The interval in second of lookup service names(only for Dubbo-OPS)
+	 * The interval in second of lookup service names(only for Dubbo-OPS).
 	 */
 	private final long servicesLookupInterval;
 
@@ -88,12 +91,15 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 
 	private final JSONUtils jsonUtils;
 
+	private final DubboGenericServiceFactory dubboGenericServiceFactory;
+
 	private final ConfigurableApplicationContext applicationContext;
 
 	public AbstractSpringCloudRegistry(URL url, DiscoveryClient discoveryClient,
 			DubboServiceMetadataRepository dubboServiceMetadataRepository,
 			DubboMetadataServiceProxy dubboMetadataConfigServiceProxy,
-			JSONUtils jsonUtils, ConfigurableApplicationContext applicationContext) {
+			JSONUtils jsonUtils, DubboGenericServiceFactory dubboGenericServiceFactory,
+			ConfigurableApplicationContext applicationContext) {
 		super(url);
 		this.servicesLookupInterval = url
 				.getParameter(SERVICES_LOOKUP_INTERVAL_PARAM_NAME, 60L);
@@ -101,6 +107,7 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 		this.repository = dubboServiceMetadataRepository;
 		this.dubboMetadataConfigServiceProxy = dubboMetadataConfigServiceProxy;
 		this.jsonUtils = jsonUtils;
+		this.dubboGenericServiceFactory = dubboGenericServiceFactory;
 		this.applicationContext = applicationContext;
 	}
 
@@ -127,8 +134,7 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 	}
 
 	/**
-	 * The sub-type should implement to register
-	 *
+	 * The sub-type should implement to register.
 	 * @param url {@link URL}
 	 */
 	protected abstract void doRegister0(URL url);
@@ -142,8 +148,7 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 	}
 
 	/**
-	 * The sub-type should implement to unregister
-	 *
+	 * The sub-type should implement to unregister.
 	 * @param url {@link URL}
 	 */
 	protected abstract void doUnregister0(URL url);
@@ -171,8 +176,7 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 
 	/**
 	 * Register a {@link ApplicationListener listener} for
-	 * {@link ServiceInstancesChangedEvent}
-	 *
+	 * {@link ServiceInstancesChangedEvent}.
 	 * @param url {@link URL}
 	 * @param listener {@link NotifyListener}
 	 */
@@ -221,7 +225,8 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 		if (CollectionUtils.isEmpty(serviceInstances)) {
 			dubboMetadataConfigServiceProxy.removeProxy(serviceName);
 			repository.removeInitializedService(serviceName);
-			repository.removeServiceMetadata(serviceName);
+			repository.removeMetadata(serviceName);
+			dubboGenericServiceFactory.destroy(serviceName);
 			if (logger.isWarnEnabled()) {
 				logger.warn(
 						"There is no instance from service[name : {}], and then Dubbo Service[key : {}] will not be "
@@ -350,8 +355,8 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 
 	@Override
 	public final void doUnsubscribe(URL url, NotifyListener listener) {
-		if (isAdminURL(url)) {
-		}
+		// if (isAdminURL(url)) {
+		// }
 	}
 
 	@Override
@@ -366,4 +371,5 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 	protected boolean isDubboMetadataServiceURL(URL url) {
 		return DUBBO_METADATA_SERVICE_CLASS_NAME.equals(url.getServiceInterface());
 	}
+
 }

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/registry/DelegatingRegistration.java

@@ -31,7 +31,7 @@ class DelegatingRegistration implements Registration {
 
 	private final ServiceInstance delegate;
 
-	public DelegatingRegistration(ServiceInstance delegate) {
+	DelegatingRegistration(ServiceInstance delegate) {
 		this.delegate = delegate;
 	}
 
@@ -69,4 +69,5 @@ class DelegatingRegistration implements Registration {
 	public String getScheme() {
 		return delegate.getScheme();
 	}
+
 }

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/registry/SpringCloudRegistry.java

@@ -13,20 +13,22 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.cloud.dubbo.registry;
 
+import com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository;
+import com.alibaba.cloud.dubbo.service.DubboGenericServiceFactory;
+import com.alibaba.cloud.dubbo.service.DubboMetadataServiceProxy;
+import com.alibaba.cloud.dubbo.util.JSONUtils;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.registry.RegistryFactory;
+
 import org.springframework.cloud.client.discovery.DiscoveryClient;
 import org.springframework.context.ConfigurableApplicationContext;
 
-import com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository;
-import com.alibaba.cloud.dubbo.service.DubboMetadataServiceProxy;
-import com.alibaba.cloud.dubbo.util.JSONUtils;
-
 /**
  * Dubbo {@link RegistryFactory} uses Spring Cloud Service Registration abstraction, whose
- * protocol is "spring-cloud"
+ * protocol is "spring-cloud".
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  */
@@ -37,9 +39,11 @@ public class SpringCloudRegistry extends AbstractSpringCloudRegistry {
 	public SpringCloudRegistry(URL url, DiscoveryClient discoveryClient,
 			DubboServiceMetadataRepository dubboServiceMetadataRepository,
 			DubboMetadataServiceProxy dubboMetadataConfigServiceProxy,
-			JSONUtils jsonUtils, ConfigurableApplicationContext applicationContext) {
+			JSONUtils jsonUtils, DubboGenericServiceFactory dubboGenericServiceFactory,
+			ConfigurableApplicationContext applicationContext) {
 		super(url, discoveryClient, dubboServiceMetadataRepository,
-				dubboMetadataConfigServiceProxy, jsonUtils, applicationContext);
+				dubboMetadataConfigServiceProxy, jsonUtils, dubboGenericServiceFactory,
+				applicationContext);
 		this.dubboServiceMetadataRepository = dubboServiceMetadataRepository;
 	}
 
@@ -52,4 +56,5 @@ public class SpringCloudRegistry extends AbstractSpringCloudRegistry {
 	protected void doUnregister0(URL url) {
 		dubboServiceMetadataRepository.unexportURL(url);
 	}
+
 }

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/registry/SpringCloudRegistryFactory.java

@@ -13,23 +13,25 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package com.alibaba.cloud.dubbo.registry;
 
-import static java.lang.System.getProperty;
-
+import com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository;
+import com.alibaba.cloud.dubbo.service.DubboGenericServiceFactory;
+import com.alibaba.cloud.dubbo.service.DubboMetadataServiceProxy;
+import com.alibaba.cloud.dubbo.util.JSONUtils;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.registry.Registry;
 import org.apache.dubbo.registry.RegistryFactory;
+
 import org.springframework.cloud.client.discovery.DiscoveryClient;
 import org.springframework.context.ConfigurableApplicationContext;
 
-import com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository;
-import com.alibaba.cloud.dubbo.service.DubboMetadataServiceProxy;
-import com.alibaba.cloud.dubbo.util.JSONUtils;
+import static java.lang.System.getProperty;
 
 /**
  * Dubbo {@link RegistryFactory} uses Spring Cloud Service Registration abstraction, whose
- * protocol is "spring-cloud"
+ * protocol is "spring-cloud".
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  * @see RegistryFactory
@@ -37,8 +39,14 @@ import com.alibaba.cloud.dubbo.util.JSONUtils;
  */
 public class SpringCloudRegistryFactory implements RegistryFactory {
 
+	/**
+	 * Spring Cloud Protocol.
+	 */
 	public static String PROTOCOL = "spring-cloud";
 
+	/**
+	 * Spring Cloud Address.
+	 */
 	public static String ADDRESS = "localhost";
 
 	private static String SERVICES_LOOKUP_SCHEDULER_THREAD_NAME_PREFIX = getProperty(
@@ -55,6 +63,8 @@ public class SpringCloudRegistryFactory implements RegistryFactory {
 
 	private JSONUtils jsonUtils;
 
+	private DubboGenericServiceFactory dubboGenericServiceFactory;
+
 	private volatile boolean initialized = false;
 
 	public SpringCloudRegistryFactory() {
@@ -75,6 +85,8 @@ public class SpringCloudRegistryFactory implements RegistryFactory {
 		this.dubboMetadataConfigServiceProxy = applicationContext
 				.getBean(DubboMetadataServiceProxy.class);
 		this.jsonUtils = applicationContext.getBean(JSONUtils.class);
+		this.dubboGenericServiceFactory = applicationContext
+				.getBean(DubboGenericServiceFactory.class);
 	}
 
 	@Override
@@ -82,6 +94,7 @@ public class SpringCloudRegistryFactory implements RegistryFactory {
 		init();
 		return new SpringCloudRegistry(url, discoveryClient,
 				dubboServiceMetadataRepository, dubboMetadataConfigServiceProxy,
-				jsonUtils, applicationContext);
+				jsonUtils, dubboGenericServiceFactory, applicationContext);
 	}
+
 }

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/registry/event/SubscribedServicesChangedEvent.java

@@ -38,7 +38,6 @@ public class SubscribedServicesChangedEvent extends ApplicationEvent {
 
 	/**
 	 * Create a new ApplicationEvent.
-	 *
 	 * @param source the object on which the event initially occurred (never {@code null})
 	 * @param oldSubscribedServices the subscribed services before changed
 	 * @param newSubscribedServices the subscribed services after changed

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/service/DubboGenericServiceFactory.java

@@ -13,23 +13,23 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package com.alibaba.cloud.dubbo.service;
 
-import static java.util.Collections.emptyMap;
-import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
-import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
-import static org.springframework.util.StringUtils.commaDelimitedListToStringArray;
+package com.alibaba.cloud.dubbo.service;
 
 import java.beans.PropertyEditorSupport;
 import java.util.Collection;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
+import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 
 import javax.annotation.PreDestroy;
 
+import com.alibaba.cloud.dubbo.metadata.DubboRestServiceMetadata;
+import com.alibaba.cloud.dubbo.metadata.ServiceRestMetadata;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.utils.CollectionUtils;
 import org.apache.dubbo.config.RegistryConfig;
@@ -37,6 +37,7 @@ import org.apache.dubbo.config.spring.ReferenceBean;
 import org.apache.dubbo.rpc.service.GenericService;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+
 import org.springframework.beans.MutablePropertyValues;
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -44,11 +45,13 @@ import org.springframework.beans.propertyeditors.StringTrimmerEditor;
 import org.springframework.util.StringUtils;
 import org.springframework.validation.DataBinder;
 
-import com.alibaba.cloud.dubbo.metadata.DubboRestServiceMetadata;
-import com.alibaba.cloud.dubbo.metadata.ServiceRestMetadata;
+import static java.util.Collections.emptyMap;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+import static org.springframework.util.StringUtils.commaDelimitedListToStringArray;
 
 /**
- * Dubbo {@link GenericService} Factory
+ * Dubbo {@link GenericService} Factory.
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  */
@@ -56,7 +59,7 @@ public class DubboGenericServiceFactory {
 
 	private final Logger logger = LoggerFactory.getLogger(getClass());
 
-	private final ConcurrentMap<Integer, ReferenceBean<GenericService>> cache = new ConcurrentHashMap<>();
+	private final ConcurrentMap<String, ReferenceBean<GenericService>> cache = new ConcurrentHashMap<>();
 
 	@Autowired
 	private ObjectProvider<List<RegistryConfig>> registryConfigs;
@@ -95,12 +98,13 @@ public class DubboGenericServiceFactory {
 		Integer key = Objects.hash(interfaceName, version, group,
 				dubboTranslatedAttributes);
 
-		return cache.computeIfAbsent(key, k -> {
+		return cache.computeIfAbsent(group + key, k -> {
 			ReferenceBean<GenericService> referenceBean = new ReferenceBean<>();
 			referenceBean.setGeneric(true);
 			referenceBean.setInterface(interfaceName);
 			referenceBean.setVersion(version);
 			referenceBean.setGroup(group);
+			referenceBean.setCheck(false);
 			bindReferenceBean(referenceBean, dubboTranslatedAttributes);
 			return referenceBean;
 		});
@@ -148,7 +152,17 @@ public class DubboGenericServiceFactory {
 	@PreDestroy
 	public void destroy() {
 		destroyReferenceBeans();
-		cache.values();
+		cache.clear();
+	}
+
+	public synchronized void destroy(String serviceName) {
+		Set<String> removeGroups = new HashSet<>(cache.keySet());
+		for (String key : removeGroups) {
+			if (key.contains(serviceName)) {
+				ReferenceBean<GenericService> referenceBean = cache.remove(key);
+				referenceBean.destroy();
+			}
+		}
 	}
 
 	private void destroyReferenceBeans() {

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/service/DubboMetadataServiceInvocationHandler.java

@@ -24,7 +24,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * {@link DubboMetadataService} {@link InvocationHandler}
+ * {@link DubboMetadataService} {@link InvocationHandler}.
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  */
@@ -34,7 +34,7 @@ class DubboMetadataServiceInvocationHandler implements InvocationHandler {
 
 	private final GenericService genericService;
 
-	public DubboMetadataServiceInvocationHandler(String serviceName, String version,
+	DubboMetadataServiceInvocationHandler(String serviceName, String version,
 			DubboGenericServiceFactory dubboGenericServiceFactory) {
 		this.genericService = dubboGenericServiceFactory.create(serviceName,
 				DubboMetadataService.class, version);
@@ -60,4 +60,5 @@ class DubboMetadataServiceInvocationHandler implements InvocationHandler {
 		return Stream.of(parameterTypes).map(Class::getName)
 				.toArray(length -> new String[length]);
 	}
+
 }

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/service/DubboMetadataServiceProxy.java

@@ -15,23 +15,25 @@
  */
 package com.alibaba.cloud.dubbo.service;
 
-import static java.lang.reflect.Proxy.newProxyInstance;
-
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
 import org.springframework.beans.factory.BeanClassLoaderAware;
 import org.springframework.beans.factory.DisposableBean;
 
+import static java.lang.reflect.Proxy.newProxyInstance;
+
 /**
- * The proxy of {@link DubboMetadataService}
+ * The proxy of {@link DubboMetadataService}.
  *
  * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  */
 public class DubboMetadataServiceProxy implements BeanClassLoaderAware, DisposableBean {
 
 	private final DubboGenericServiceFactory dubboGenericServiceFactory;
+
 	private final Map<String, DubboMetadataService> dubboMetadataServiceCache = new ConcurrentHashMap<>();
+
 	private ClassLoader classLoader;
 
 	public DubboMetadataServiceProxy(
@@ -40,8 +42,7 @@ public class DubboMetadataServiceProxy implements BeanClassLoaderAware, Disposab
 	}
 
 	/**
-	 * Initializes {@link DubboMetadataService}'s Proxy
-	 *
+	 * Initializes {@link DubboMetadataService}'s Proxy.
 	 * @param serviceName the service name
 	 * @param version the service version
 	 * @return a {@link DubboMetadataService} proxy
@@ -52,7 +53,7 @@ public class DubboMetadataServiceProxy implements BeanClassLoaderAware, Disposab
 	}
 
 	/**
-	 * Remove {@link DubboMetadataService}'s Proxy by service name
+	 * Remove {@link DubboMetadataService}'s Proxy by service name.
 	 * @param serviceName the service name
 	 */
 	public void removeProxy(String serviceName) {
@@ -60,8 +61,8 @@ public class DubboMetadataServiceProxy implements BeanClassLoaderAware, Disposab
 	}
 
 	/**
-	 * Get a proxy instance of {@link DubboMetadataService} via the specified service name
-	 *
+	 * Get a proxy instance of {@link DubboMetadataService} via the specified service
+	 * name.
 	 * @param serviceName the service name
 	 * @return a {@link DubboMetadataService} proxy
 	 */
@@ -80,8 +81,8 @@ public class DubboMetadataServiceProxy implements BeanClassLoaderAware, Disposab
 	}
 
 	/**
-	 * New a proxy instance of {@link DubboMetadataService} via the specified service name
-	 *
+	 * New a proxy instance of {@link DubboMetadataService} via the specified service
+	 * name.
 	 * @param serviceName the service name
 	 * @param version the service version
 	 * @return a {@link DubboMetadataService} proxy
@@ -92,4 +93,5 @@ public class DubboMetadataServiceProxy implements BeanClassLoaderAware, Disposab
 				new DubboMetadataServiceInvocationHandler(serviceName, version,
 						dubboGenericServiceFactory));
 	}
+
 }

spring-cloud-alibaba-dubbo/src/main/java/com/alibaba/cloud/dubbo/service/parameter/DubboGenericServiceParameterResolver.java

@@ -15,13 +15,14 @@
  */
 package com.alibaba.cloud.dubbo.service.parameter;
 
-import org.apache.dubbo.rpc.service.GenericService;
-import org.springframework.core.Ordered;
-
 import com.alibaba.cloud.dubbo.http.HttpServerRequest;
 import com.alibaba.cloud.dubbo.metadata.MethodParameterMetadata;
 import com.alibaba.cloud.dubbo.metadata.RestMethodMetadata;
 
+import org.apache.dubbo.rpc.service.GenericService;
+
+import org.springframework.core.Ordered;
+
 /**
  * Dubbo {@link GenericService} Parameter Resolver
  *
@@ -31,8 +32,10 @@ public interface DubboGenericServiceParameterResolver extends Ordered {
 
 	/**
 	 * Resolves a method parameter into an argument value from a given request.
-	 *
-	 * @return
+	 * @param restMethodMetadata method request metadata
+	 * @param methodParameterMetadata metadata of method
+	 * @param request Http server request
+	 * @return the result of resolve
 	 */
 	Object resolve(RestMethodMetadata restMethodMetadata,
 			MethodParameterMetadata methodParameterMetadata, HttpServerRequest request);