[ISSUE #4129]Enhance the functionality of EventMeshExtensionFactory (#4131)

mxsm · web-flow · commit 643f059ac43f · 2023-08-29T15:06:17.000+08:00
diff --git a/eventmesh-spi/src/main/java/org/apache/eventmesh/spi/EventMeshExtensionFactory.java b/eventmesh-spi/src/main/java/org/apache/eventmesh/spi/EventMeshExtensionFactory.java
@@ -29,6 +29,7 @@
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.concurrent.ConcurrentHashMap;
 
 
@@ -43,7 +44,7 @@ public class EventMeshExtensionFactory {
 
     private static final List<ExtensionClassLoader> EXTENSION_CLASS_LOADERS = new ArrayList<>();
 
-    private static final ConcurrentHashMap<String, Object> EXTENSION_INSTANCE_CACHE = new ConcurrentHashMap<>(16);
+    private static final ConcurrentHashMap<Extension, Object> EXTENSION_INSTANCE_CACHE = new ConcurrentHashMap<>(16);
 
     static {
         EXTENSION_CLASS_LOADERS.add(MetaInfExtensionClassLoader.getInstance());
@@ -56,52 +57,72 @@ private EventMeshExtensionFactory() {
     }
 
     /**
-     * @param extensionType extension plugin class type
-     * @param extensionName extension instance name
-     * @param <T>           the type of the plugin
+     * Get an instance of an extension plugin.
+     *
+     * @param extensionClass extension plugin class type
+     * @param extensionName  extension instance name
+     * @param <T>            the type of the plugin
      * @return plugin instance
      */
-    public static <T> T getExtension(Class<T> extensionType, String extensionName) {
-        if (extensionType == null) {
-            throw new ExtensionException("extensionType is null");
+    public static <T> T getExtension(Class<T> extensionClass, String extensionName) {
+        if (extensionClass == null) {
+            throw new ExtensionException("extensionClass is null");
         }
         if (StringUtils.isEmpty(extensionName)) {
             throw new ExtensionException("extensionName is null");
         }
-        if (!extensionType.isInterface() || !extensionType.isAnnotationPresent(EventMeshSPI.class)) {
-            throw new ExtensionException(String.format("extensionType:%s is invalided", extensionType));
+        if (!extensionClass.isInterface() || !extensionClass.isAnnotationPresent(EventMeshSPI.class)) {
+            throw new ExtensionException(String.format("extensionClass:%s is invalided", extensionClass));
         }
-        EventMeshSPI eventMeshSPIAnnotation = extensionType.getAnnotation(EventMeshSPI.class);
+        EventMeshSPI eventMeshSPIAnnotation = extensionClass.getAnnotation(EventMeshSPI.class);
         if (eventMeshSPIAnnotation.isSingleton()) {
-            return getSingletonExtension(extensionType, extensionName);
+            return getSingletonExtension(extensionClass, eventMeshSPIAnnotation, extensionName);
         }
-        return getPrototypeExtension(extensionType, extensionName);
+        return getPrototypeExtension(extensionClass, extensionName);
     }
 
+    /**
+     * Get a singleton instance of an extension plugin.
+     *
+     * @param extensionClass the type of the extension plugin
+     * @param spi the type of the spi
+     * @param extensionInstanceName the name of the extension instance
+     * @param <T> the type of the extension plugin
+     * @return a singleton instance of the extension plugin
+     */
     @SuppressWarnings("unchecked")
-    private static <T> T getSingletonExtension(Class<T> extensionType, String extensionInstanceName) {
-        return (T) EXTENSION_INSTANCE_CACHE.computeIfAbsent(extensionInstanceName, name -> {
-            Class<T> extensionInstanceClass = getExtensionInstanceClass(extensionType, extensionInstanceName);
+    private static <T> T getSingletonExtension(Class<T> extensionClass, EventMeshSPI spi, String extensionInstanceName) {
+        return (T) EXTENSION_INSTANCE_CACHE.computeIfAbsent(new Extension(spi, extensionInstanceName), name -> {
+            Class<T> extensionInstanceClass = getExtensionInstanceClass(extensionClass, extensionInstanceName);
             if (extensionInstanceClass == null) {
+                log.warn("Get extension instance class {} is null", extensionClass.getName());
                 return null;
             }
             try {
                 T extensionInstance = extensionInstanceClass.getDeclaredConstructor().newInstance();
                 ConfigService.getInstance().populateConfigForObject(extensionInstance);
 
-                log.info("initialize extension instance success, extensionType: {}, extensionInstanceName: {}",
-                    extensionType, extensionInstanceName);
+                log.info("initialize extension instance success, extensionClass: {}, extensionInstanceName: {}",
+                    extensionClass, extensionInstanceName);
                 return extensionInstance;
             } catch (NoSuchMethodException | InstantiationException | IllegalAccessException | InvocationTargetException e) {
                 throw new ExtensionException("Extension initialize error", e);
             } catch (NoSuchFieldException | IOException e) {
-                log.error("initialize extension instance config failed, extensionType: {}, extensionInstanceName: {}",
-                    extensionType, extensionInstanceName, e);
+                log.error("initialize extension instance config failed, extensionClass: {}, extensionInstanceName: {}",
+                    extensionClass, extensionInstanceName, e);
                 throw new ExtensionException("Extension initialize error", e);
             }
         });
     }
 
+    /**
+     * Get a new instance of an extension plugin.
+     *
+     * @param extensionType the type of the extension plugin
+     * @param extensionInstanceName the name of the extension instance
+     * @param <T> the type of the extension plugin
+     * @return a new instance of the extension plugin
+     */
     private static <T> T getPrototypeExtension(Class<T> extensionType, String extensionInstanceName) {
         Class<T> extensionInstanceClass = getExtensionInstanceClass(extensionType, extensionInstanceName);
         if (extensionInstanceClass == null) {
@@ -123,6 +144,14 @@ private static <T> T getPrototypeExtension(Class<T> extensionType, String extens
         }
     }
 
+    /**
+     * Get the class of an extension instance.
+     *
+     * @param extensionType the type of the extension instance
+     * @param extensionInstanceName the name of the extension instance
+     * @param <T> the type of the extension instance
+     * @return the class of the extension instance
+     */
     @SuppressWarnings("unchecked")
     private static <T> Class<T> getExtensionInstanceClass(Class<T> extensionType, String extensionInstanceName) {
         for (ExtensionClassLoader extensionClassLoader : EXTENSION_CLASS_LOADERS) {
@@ -134,4 +163,33 @@ private static <T> Class<T> getExtensionInstanceClass(Class<T> extensionType, St
         }
         return null;
     }
+
+    private static class Extension {
+
+        private EventMeshSPI spi;
+
+        private String extensionInstanceName;
+
+        public Extension(EventMeshSPI spi, String extensionInstanceName) {
+            this.spi = spi;
+            this.extensionInstanceName = extensionInstanceName;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (!(o instanceof Extension)) {
+                return false;
+            }
+            Extension extension = (Extension) o;
+            return Objects.equals(spi, extension.spi) && Objects.equals(extensionInstanceName, extension.extensionInstanceName);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(spi, extensionInstanceName);
+        }
+    }
 }
diff --git a/eventmesh-spi/src/test/java/org/apache/eventmesh/spi/EventMeshExtensionFactoryTest.java b/eventmesh-spi/src/test/java/org/apache/eventmesh/spi/EventMeshExtensionFactoryTest.java
@@ -17,6 +17,7 @@
 
 package org.apache.eventmesh.spi;
 
+import org.apache.eventmesh.spi.example.TestAnotherSingletonExtension;
 import org.apache.eventmesh.spi.example.TestPrototypeExtension;
 import org.apache.eventmesh.spi.example.TestSingletonExtension;
 
@@ -30,6 +31,14 @@ public void testGetSingletonExtension() {
         TestSingletonExtension extensionA = EventMeshExtensionFactory.getExtension(TestSingletonExtension.class, "singletonExtension");
         TestSingletonExtension extensionB = EventMeshExtensionFactory.getExtension(TestSingletonExtension.class, "singletonExtension");
         Assert.assertSame(extensionA, extensionB);
+
+        TestAnotherSingletonExtension singletonExtension = EventMeshExtensionFactory.getExtension(TestAnotherSingletonExtension.class,
+            "singletonExtension");
+        Assert.assertNotNull(singletonExtension);
+        TestSingletonExtension singletonExtension1 = EventMeshExtensionFactory.getExtension(TestSingletonExtension.class, "singletonExtension");
+        Assert.assertNotNull(singletonExtension1);
+
+
     }
 
     @Test
diff --git a/eventmesh-spi/src/test/java/org/apache/eventmesh/spi/example/AnotherSingletonExtension.java b/eventmesh-spi/src/test/java/org/apache/eventmesh/spi/example/AnotherSingletonExtension.java
@@ -0,0 +1,30 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 org.apache.eventmesh.spi.example;
+
+
+import lombok.extern.slf4j.Slf4j;
+
+@Slf4j
+public class AnotherSingletonExtension implements TestAnotherSingletonExtension {
+
+    @Override
+    public void hello() {
+        log.info("I am SingletonExtension");
+    }
+}
diff --git a/eventmesh-spi/src/test/java/org/apache/eventmesh/spi/example/TestAnotherSingletonExtension.java b/eventmesh-spi/src/test/java/org/apache/eventmesh/spi/example/TestAnotherSingletonExtension.java
@@ -0,0 +1,30 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 org.apache.eventmesh.spi.example;
+
+import org.apache.eventmesh.spi.EventMeshExtensionType;
+import org.apache.eventmesh.spi.EventMeshSPI;
+
+/**
+ * TestAnotherSingletonExtension
+ */
+@EventMeshSPI(eventMeshExtensionType = EventMeshExtensionType.SECURITY)
+public interface TestAnotherSingletonExtension {
+
+    void hello();
+}
diff --git a/eventmesh-spi/src/test/resources/META-INF/eventmesh/org.apache.eventmesh.spi.example.TestAnotherSingletonExtension b/eventmesh-spi/src/test/resources/META-INF/eventmesh/org.apache.eventmesh.spi.example.TestAnotherSingletonExtension
@@ -0,0 +1,17 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You 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
+#
+#     http://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.
+
+singletonExtension=org.apache.eventmesh.spi.example.AnotherSingletonExtension
