Nacos registry enhancement & register reference bean (apache#4454)

fixes apache#4439, apache#4455

dubbo-bom/pom.xml

@@ -44,8 +44,8 @@
         <url>https://github.com/apache/dubbo</url>
         <connection>scm:git:https://github.com/apache/dubbo.git</connection>
         <developerConnection>scm:git:https://github.com/apache/dubbo.git</developerConnection>
-      <tag>HEAD</tag>
-  </scm>
+        <tag>HEAD</tag>
+    </scm>
     <mailingLists>
         <mailingList>
             <name>Development List</name>

dubbo-common/src/main/java/org/apache/dubbo/common/bytecode/Proxy.java

@@ -102,7 +102,7 @@ public static Proxy getProxy(ClassLoader cl, Class<?>... ics) {
         String key = sb.toString();
 
         // get cache by class loader.
-        Map<String, Object> cache;
+        final Map<String, Object> cache;
         synchronized (PROXY_CACHE_MAP) {
             cache = PROXY_CACHE_MAP.computeIfAbsent(cl, k -> new HashMap<>());
         }

dubbo-common/src/main/java/org/apache/dubbo/common/extension/ExtensionLoader.java

@@ -342,7 +342,7 @@ public T getExtension(String name) {
         if ("true".equals(name)) {
             return getDefaultExtension();
         }
-        Holder<Object> holder = getOrCreateHolder(name);
+        final Holder<Object> holder = getOrCreateHolder(name);
         Object instance = holder.get();
         if (instance == null) {
             synchronized (holder) {

dubbo-common/src/main/java/org/apache/dubbo/common/utils/NetUtils.java

@@ -37,9 +37,9 @@
 import java.util.regex.Pattern;
 
 import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.DUBBO_IP_TO_BIND;
 import static org.apache.dubbo.common.constants.CommonConstants.LOCALHOST_KEY;
 import static org.apache.dubbo.common.constants.CommonConstants.LOCALHOST_VALUE;
-import static org.apache.dubbo.common.constants.CommonConstants.DUBBO_IP_TO_BIND;
 
 /**
  * IP and Port Helper for RPC

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/annotation/Reference.java

@@ -30,6 +30,7 @@
  * Reference
  *
  * @export
+ * @since 2.7.0
  */
 @Documented
 @Retention(RetentionPolicy.RUNTIME)
@@ -228,32 +229,35 @@
     String[] parameters() default {};
 
     /**
-     * Application spring bean name
+     * Application associated name
      */
     String application() default "";
 
     /**
-     * Module spring bean name
+     * Module associated name
      */
     String module() default "";
 
     /**
-     * Consumer spring bean name
+     * Consumer associated name
      */
     String consumer() default "";
 
     /**
-     * Monitor spring bean name
+     * Monitor associated name
      */
     String monitor() default "";
 
     /**
-     * Registry spring bean name
+     * Registry associated name
      */
     String[] registry() default {};
 
     /**
-     * Protocol spring bean names
+     * The communication protocol of Dubbo Service
+     *
+     * @return the default value is ""
+     * @since 2.6.6
      */
     String protocol() default "";
 
@@ -264,7 +268,16 @@
 
     /**
      * methods support
+     *
      * @return
      */
     Method[] methods() default {};
+
+    /**
+     * The id
+     *
+     * @return default value is empty
+     * @since 2.7.3
+     */
+    String id() default "";
 }

dubbo-config/dubbo-config-spring/src/main/java/org/apache/dubbo/config/spring/beans/factory/annotation/AnnotationInjectedBeanPostProcessor.java

@@ -26,6 +26,7 @@
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.BeanFactoryAware;
 import org.springframework.beans.factory.DisposableBean;
+import org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor;
 import org.springframework.beans.factory.annotation.InjectionMetadata;
 import org.springframework.beans.factory.config.BeanPostProcessor;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
@@ -91,7 +92,12 @@ public abstract class AnnotationInjectedBeanPostProcessor extends
 
     private ClassLoader classLoader;
 
-    private int order = Ordered.LOWEST_PRECEDENCE;
+    /**
+     * make sure higher priority than {@link AutowiredAnnotationBeanPostProcessor}
+     *
+     * @revision 2.7.3
+     */
+    private int order = Ordered.LOWEST_PRECEDENCE - 3;
 
     /**
      * @param annotationTypes the multiple types of {@link Annotation annotations}

dubbo-config/dubbo-config-spring/src/main/java/org/apache/dubbo/config/spring/beans/factory/annotation/ReferenceAnnotationBeanPostProcessor.java

@@ -24,6 +24,9 @@
 
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.annotation.InjectionMetadata;
+import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
+import org.springframework.beans.factory.config.RuntimeBeanReference;
+import org.springframework.beans.factory.support.AbstractBeanDefinition;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
 import org.springframework.context.ApplicationEvent;
@@ -43,6 +46,8 @@
 import java.util.concurrent.ConcurrentMap;
 
 import static org.apache.dubbo.config.spring.beans.factory.annotation.ServiceBeanNameBuilder.create;
+import static org.apache.dubbo.config.spring.util.AnnotationUtils.getAttribute;
+import static org.springframework.util.StringUtils.hasText;
 
 /**
  * {@link org.springframework.beans.factory.config.BeanPostProcessor} implementation
@@ -120,13 +125,96 @@ protected Object doGetInjectedBean(AnnotationAttributes attributes, Object bean,
 
         String referencedBeanName = buildReferencedBeanName(attributes, injectedType);
 
-        ReferenceBean referenceBean = buildReferenceBeanIfAbsent(referencedBeanName, attributes, injectedType, getClassLoader());
+        ReferenceBean referenceBean = buildReferenceBeanIfAbsent(referencedBeanName, attributes, injectedType);
+
+        registerReferenceBean(referencedBeanName, referenceBean, attributes, injectedType);
 
         cacheInjectedReferenceBean(referenceBean, injectedElement);
 
         return buildProxy(referencedBeanName, referenceBean, injectedType);
     }
 
+    /**
+     * Register an instance of {@link ReferenceBean} as a Spring Bean
+     *
+     * @param referencedBeanName the referenced bean name
+     * @param referenceBean      the instance of {@link ReferenceBean}
+     * @param attributes         the {@link AnnotationAttributes attributes} of {@link Reference @Reference}
+     * @param interfaceClass     the {@link Class class} of Service interface
+     * @since 2.7.3
+     */
+    private void registerReferenceBean(String referencedBeanName, ReferenceBean referenceBean,
+                                       AnnotationAttributes attributes,
+                                       Class<?> interfaceClass) {
+
+        ConfigurableListableBeanFactory beanFactory = getBeanFactory();
+
+        String beanName = getReferenceBeanName(attributes, interfaceClass);
+
+        if (beanFactory.containsBean(referencedBeanName)) { // If @Service bean is local one
+            /**
+             * Get  the @Service's BeanDefinition from {@link BeanFactory}
+             * Refer to {@link ServiceAnnotationBeanPostProcessor#buildServiceBeanDefinition}
+             */
+            AbstractBeanDefinition beanDefinition = (AbstractBeanDefinition) beanFactory.getBeanDefinition(referencedBeanName);
+            RuntimeBeanReference runtimeBeanReference = (RuntimeBeanReference) beanDefinition.getPropertyValues().get("ref");
+            // The name of bean annotated @Service
+            String serviceBeanName = runtimeBeanReference.getBeanName();
+            // register Alias rather than a new bean name, in order to reduce duplicated beans
+            beanFactory.registerAlias(serviceBeanName, beanName);
+        } else { // Remote @Service Bean
+            if (!beanFactory.containsBean(beanName)) {
+                beanFactory.registerSingleton(beanName, referenceBean);
+            }
+        }
+    }
+
+    /**
+     * Get the bean name of {@link ReferenceBean} if {@link Reference#id() id attribute} is present,
+     * or {@link #generateReferenceBeanName(AnnotationAttributes, Class) generate}.
+     *
+     * @param attributes     the {@link AnnotationAttributes attributes} of {@link Reference @Reference}
+     * @param interfaceClass the {@link Class class} of Service interface
+     * @return non-null
+     * @since 2.7.3
+     */
+    private String getReferenceBeanName(AnnotationAttributes attributes, Class<?> interfaceClass) {
+        // id attribute appears since 2.7.3
+        String beanName = getAttribute(attributes, "id");
+        if (!hasText(beanName)) {
+            beanName = generateReferenceBeanName(attributes, interfaceClass);
+        }
+        return beanName;
+    }
+
+    /**
+     * Build the bean name of {@link ReferenceBean}
+     *
+     * @param attributes     the {@link AnnotationAttributes attributes} of {@link Reference @Reference}
+     * @param interfaceClass the {@link Class class} of Service interface
+     * @return
+     * @since 2.7.3
+     */
+    private String generateReferenceBeanName(AnnotationAttributes attributes, Class<?> interfaceClass) {
+        StringBuilder beanNameBuilder = new StringBuilder("@Reference");
+
+        if (!attributes.isEmpty()) {
+            beanNameBuilder.append('(');
+            for (Map.Entry<String, Object> entry : attributes.entrySet()) {
+                beanNameBuilder.append(entry.getKey())
+                        .append('=')
+                        .append(entry.getValue())
+                        .append(',');
+            }
+            // replace the latest "," to be ")"
+            beanNameBuilder.setCharAt(beanNameBuilder.lastIndexOf(","), ')');
+        }
+
+        beanNameBuilder.append(" ").append(interfaceClass.getName());
+
+        return beanNameBuilder.toString();
+    }
+
     private Object buildProxy(String referencedBeanName, ReferenceBean referenceBean, Class<?> injectedType) {
         InvocationHandler handler = buildInvocationHandler(referencedBeanName, referenceBean);
         return Proxy.newProxyInstance(getClassLoader(), new Class[]{injectedType}, handler);
@@ -199,7 +287,7 @@ private String buildReferencedBeanName(AnnotationAttributes attributes, Class<?>
     }
 
     private ReferenceBean buildReferenceBeanIfAbsent(String referencedBeanName, AnnotationAttributes attributes,
-                                                     Class<?> referencedType, ClassLoader classLoader)
+                                                     Class<?> referencedType)
             throws Exception {
 
         ReferenceBean<?> referenceBean = referenceBeanCache.get(referencedBeanName);

dubbo-config/dubbo-config-spring/src/test/java/org/apache/dubbo/config/spring/beans/factory/annotation/ReferenceAnnotationBeanPostProcessorTest.java

@@ -80,10 +80,27 @@ public void test() throws Exception {
         Assert.assertNotNull(testBean.getDemoServiceFromAncestor());
         Assert.assertNotNull(testBean.getDemoServiceFromParent());
         Assert.assertNotNull(testBean.getDemoService());
+        Assert.assertNotNull(testBean.autowiredDemoService);
 
         Assert.assertEquals("Hello,Mercy", testBean.getDemoServiceFromAncestor().sayName("Mercy"));
         Assert.assertEquals("Hello,Mercy", testBean.getDemoServiceFromParent().sayName("Mercy"));
         Assert.assertEquals("Hello,Mercy", testBean.getDemoService().sayName("Mercy"));
+        Assert.assertEquals("Hello,Mercy", testBean.autowiredDemoService.sayName("Mercy"));
+
+        DemoService myDemoService = context.getBean("my-reference-bean", DemoService.class);
+
+        Assert.assertEquals("Hello,Mercy", myDemoService.sayName("Mercy"));
+
+        Map<String, DemoService> demoServicesMap = context.getBeansOfType(DemoService.class);
+
+        Assert.assertEquals(1, demoServicesMap.size());
+
+        for (DemoService demoService1 : demoServicesMap.values()) {
+
+            Assert.assertEquals(myDemoService, demoService1);
+
+            Assert.assertEquals("Hello,Mercy", demoService1.sayName("Mercy"));
+        }
 
     }
 
@@ -194,7 +211,7 @@ public DemoService getDemoServiceFromAncestor() {
             return demoServiceFromAncestor;
         }
 
-        @Reference(version = "2.5.7", url = "dubbo://127.0.0.1:12345")
+        @Reference(id = "my-reference-bean", version = "2.5.7", url = "dubbo://127.0.0.1:12345")
         public void setDemoServiceFromAncestor(DemoService demoServiceFromAncestor) {
             this.demoServiceFromAncestor = demoServiceFromAncestor;
         }
@@ -222,6 +239,9 @@ static class TestBean extends ParentBean {
 
         private DemoService demoService;
 
+        @Autowired
+        private DemoService autowiredDemoService;
+
         @Autowired
         private ApplicationContext applicationContext;
 

dubbo-config/dubbo-config-spring/src/test/java/org/apache/dubbo/config/spring/context/annotation/EnableDubboTest.java

@@ -100,6 +100,11 @@ public void testConsumer() {
 
         Assertions.assertEquals("Hello,Mercy", value);
 
+        DemoService autowiredDemoService = consumerConfiguration.getAutowiredDemoService();
+
+        Assertions.assertEquals("Hello,Mercy", autowiredDemoService.sayName("Mercy"));
+
+
         TestConsumerConfiguration.Child child = context.getBean(TestConsumerConfiguration.Child.class);
 
         // From Child

dubbo-config/dubbo-config-spring/src/test/java/org/apache/dubbo/config/spring/context/annotation/consumer/ConsumerConfiguration.java

@@ -22,6 +22,7 @@
 import org.apache.dubbo.config.spring.api.DemoService;
 import org.apache.dubbo.config.spring.context.annotation.DubboComponentScan;
 
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.PropertySource;
@@ -63,6 +64,9 @@ public RegistryConfig registryConfig() {
         return registryConfig;
     }
 
+    @Autowired
+    private DemoService autowiredDemoService;
+
     @Reference(version = "2.5.7", url = "dubbo://127.0.0.1:12345")
     private DemoService demoService;
 
@@ -111,9 +115,17 @@ public void setDemoServiceFromParent(DemoService demoServiceFromParent) {
 
     public static class Child extends Parent {
 
+        @Autowired
+        private DemoService demoService;
+
         @Reference(version = "2.5.7", url = "dubbo://127.0.0.1:12345")
         private DemoService demoServiceFromChild;
 
+
+        public DemoService getDemoService() {
+            return demoService;
+        }
+
         public DemoService getDemoServiceFromChild() {
             return demoServiceFromChild;
         }

dubbo-config/dubbo-config-spring/src/test/java/org/apache/dubbo/config/spring/context/annotation/consumer/test/TestConsumerConfiguration.java

@@ -20,6 +20,7 @@
 import org.apache.dubbo.config.spring.api.DemoService;
 import org.apache.dubbo.config.spring.context.annotation.EnableDubbo;
 
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.PropertySource;
 import org.springframework.transaction.annotation.EnableTransactionManagement;
@@ -37,6 +38,13 @@ public class TestConsumerConfiguration {
     @Reference(version = "2.5.7", url = "dubbo://127.0.0.1:12345", application = "dubbo-demo-application")
     private DemoService demoService;
 
+    @Autowired
+    private DemoService autowiredDemoService;
+
+    public DemoService getAutowiredDemoService() {
+        return autowiredDemoService;
+    }
+
     public DemoService getDemoService() {
         return demoService;
     }

dubbo-config/dubbo-config-spring/src/test/java/org/apache/dubbo/config/spring/context/context/annotation/DubboComponentScanRegistrarTest.java

@@ -86,6 +86,8 @@ public void test() {
 
         Assertions.assertEquals("Hello,Mercy", value);
 
+        Assertions.assertEquals("Hello,Mercy", child.getDemoService().sayName("Mercy"));
+
         // From Parent
 
         demoService = child.getDemoServiceFromParent();

dubbo-registry/dubbo-registry-multicast/src/main/java/org/apache/dubbo/registry/multicast/MulticastRegistry.java

@@ -263,7 +263,7 @@ public void doUnregister(URL url) {
     }
 
     @Override
-    public void doSubscribe(URL url, NotifyListener listener) {
+    public void doSubscribe(URL url, final NotifyListener listener) {
         if (ANY_VALUE.equals(url.getServiceInterface())) {
             admin = true;
         }
@@ -324,7 +324,7 @@ protected void registered(URL url) {
                 }
                 urls.add(url);
                 List<URL> list = toList(urls);
-                for (NotifyListener listener : entry.getValue()) {
+                for (final NotifyListener listener : entry.getValue()) {
                     notify(key, listener, list);
                     synchronized (listener) {
                         listener.notify();