fix Issue 8516 on branch 3.0: fix mock:true configuration.

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/support/MockInvoker.java

@@ -161,14 +161,15 @@ public static Throwable getThrowable(String throwstr) {
     }
 
     @SuppressWarnings("unchecked")
-    private Invoker<T> getInvoker(String mockService) {
+    private Invoker<T> getInvoker(String mock) {
+        Class<T> serviceType = (Class<T>) ReflectUtils.forName(url.getServiceInterface());
+        String mockService = ConfigUtils.isDefault(mock) ? serviceType.getName() + "Mock" : mock;
         Invoker<T> invoker = (Invoker<T>) MOCK_MAP.get(mockService);
         if (invoker != null) {
             return invoker;
         }
 
-        Class<T> serviceType = (Class<T>) ReflectUtils.forName(url.getServiceInterface());
-        T mockObject = (T) getMockObject(mockService, serviceType);
+        T mockObject = (T) getMockObject(mock, serviceType);
         invoker = PROXY_FACTORY.getInvoker(mockObject, serviceType, url);
         if (MOCK_MAP.size() < 10000) {
             MOCK_MAP.put(mockService, invoker);

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/support/DemoServiceA.java

@@ -0,0 +1,21 @@
+/*
+ * 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.dubbo.rpc.support;
+
+public interface DemoServiceA {
+    String methodA();
+}

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/support/DemoServiceAMock.java

@@ -0,0 +1,28 @@
+/*
+ * 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.dubbo.rpc.support;
+
+/**
+ * default mock service for DemoServiceA
+ */
+public class DemoServiceAMock implements DemoServiceA{
+    public static final String MOCK_VALUE = "mockA";
+    @Override
+    public String methodA() {
+        return MOCK_VALUE;
+    }
+}

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/support/DemoServiceB.java

@@ -0,0 +1,21 @@
+/*
+ * 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.dubbo.rpc.support;
+
+public interface DemoServiceB {
+    String methodB();
+}

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/support/DemoServiceBMock.java

@@ -0,0 +1,29 @@
+/*
+ * 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.dubbo.rpc.support;
+
+/**
+ * default mock service for DemoServiceA
+ */
+public class DemoServiceBMock implements DemoServiceB {
+    public static final String MOCK_VALUE = "mockB";
+
+    @Override
+    public String methodB() {
+        return MOCK_VALUE;
+    }
+}

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/support/MockInvokerTest.java

@@ -65,6 +65,31 @@ public void testInvoke() {
                 mockInvoker.invoke(invocation).getObjectAttachments());
     }
 
+    @Test
+    public void testGetDefaultObject() {
+        // test methodA in DemoServiceAMock
+        final Class<DemoServiceA> demoServiceAClass = DemoServiceA.class;
+        URL url = URL.valueOf("remote://1.2.3.4/" + demoServiceAClass.getName());
+        url = url.addParameter(MOCK_KEY, "force:true");
+        MockInvoker mockInvoker = new MockInvoker(url, demoServiceAClass);
+
+        RpcInvocation invocation = new RpcInvocation();
+        invocation.setMethodName("methodA");
+        Assertions.assertEquals(new HashMap<>(),
+                mockInvoker.invoke(invocation).getObjectAttachments());
+
+        // test methodB in DemoServiceBMock
+        final Class<DemoServiceB> demoServiceBClass = DemoServiceB.class;
+        url = URL.valueOf("remote://1.2.3.4/" + demoServiceBClass.getName());
+        url = url.addParameter(MOCK_KEY, "force:true");
+        mockInvoker = new MockInvoker(url, demoServiceBClass);
+        invocation = new RpcInvocation();
+        invocation.setMethodName("methodB");
+        Assertions.assertEquals(new HashMap<>(),
+                mockInvoker.invoke(invocation).getObjectAttachments());
+    }
+
+
     @Test
     public void testInvokeThrowsRpcException1() {
         URL url = URL.valueOf("remote://1.2.3.4/" + String.class.getName());