Async optimization (#3738)

* Result implement CF

* Result implement CF

* Result implement CF

* Add AsyncRpcResult

* Fix bugs and refactor Filter

* Try to add onSend onError for Filter

* invoke different filter method according to result status.

*  make generic work with async call, including add $invokeAsync

* refactor legacy Filter implementation to work with onResponse.

* demo changes

* Fixes #3620, provider attachment lose on consumer side, fix this by reverting RpcContext copy

* AsyncRpcResult should always holds an Invocation instance

* refactor filter signature

* reimplement embedded Filters

* use ProviderModel modification in 3.x

* Fix address notification processing workflow after merging 3.x branch

* Fix UT

* Fix UT

* Unit test of JValidator; Clean code of JValidator (#3723)

* Fixes #3625 (#3730)

use constant to replace magic number

* Fix conflict when merging master and 3.x

* Fix conflict when merging master and 3.x

* Result interface itself has Future status.

* Fix DefaultFuture UT

* Wrap all protocol Invoker with AsyncToSyncInvoker & Fix UT

* Add license

* fix UT

* Fix ut in MonitorFilterTest

* avoid duplicate async to sync wrapper

* return async result in CacheFilter.

* fix UT in CacheFilterTest

* Add generic condition check to GenericFilter callback.

* Fix UT

* Get generic from RpcContext if the value in Invocation is empty.

* Fix RSocketProtocol to meet AbstractProtocol adjustment

* rename RpcResult to AppResponse to help avoid confusion with AsyncRpcResult.

* RSocket module switch to AsyncRpcResult

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/FailbackClusterInvoker.java

@@ -24,11 +24,11 @@ import org.apache.dubbo.common.timer.Timeout;
 import org.apache.dubbo.common.timer.Timer;
 import org.apache.dubbo.common.timer.TimerTask;
 import org.apache.dubbo.common.utils.NamedThreadFactory;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 import org.apache.dubbo.rpc.cluster.LoadBalance;
 
@@ -99,7 +99,7 @@ public class FailbackClusterInvoker<T> extends AbstractClusterInvoker<T> {
             logger.error("Failback to invoke method " + invocation.getMethodName() + ", wait for retry in background. Ignored exception: "
                     + e.getMessage() + ", ", e);
             addFailed(loadbalance, invocation, invokers, invoker);
-            return new RpcResult(); // ignore
+            return AsyncRpcResult.newDefaultAsyncResult(null, null, invocation); // ignore
         }
     }
 

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/FailsafeClusterInvoker.java

@@ -18,11 +18,11 @@ package org.apache.dubbo.rpc.cluster.support;
 
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 import org.apache.dubbo.rpc.cluster.LoadBalance;
 
@@ -50,7 +50,7 @@ public class FailsafeClusterInvoker<T> extends AbstractClusterInvoker<T> {
             return invoker.invoke(invocation);
         } catch (Throwable e) {
             logger.error("Failsafe ignore exception: " + e.getMessage(), e);
-            return new RpcResult(); // ignore
+            return AsyncRpcResult.newDefaultAsyncResult(null, null, invocation); // ignore
         }
     }
 }

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/ForkingClusterInvoker.java

@@ -36,6 +36,8 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 
 /**
+ * NOTICE! This implementation does not work well with async call.
+ *
  * Invoke a specific number of invokers concurrently, usually used for demanding real-time operations, but need to waste more service resources.
  *
  * <a href="http://en.wikipedia.org/wiki/Fork_(topology)">Fork</a>
@@ -66,7 +68,6 @@ public class ForkingClusterInvoker<T> extends AbstractClusterInvoker<T> {
             } else {
                 selected = new ArrayList<>();
                 for (int i = 0; i < forks; i++) {
-                    // TODO. Add some comment here, refer chinese version for more details.
                     Invoker<T> invoker = select(loadbalance, invocation, invokers, selected);
                     if (!selected.contains(invoker)) {
                         //Avoid add the same invoker several times.

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/MergeableClusterInvoker.java

@@ -23,12 +23,12 @@ import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.common.utils.ConfigUtils;
 import org.apache.dubbo.common.utils.NamedThreadFactory;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 import org.apache.dubbo.rpc.cluster.LoadBalance;
 import org.apache.dubbo.rpc.cluster.Merger;
@@ -41,12 +41,13 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.concurrent.Callable;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
-import java.util.concurrent.Future;
-import java.util.concurrent.TimeUnit;
 
+/**
+ * NOTICE! Does not work with async call.
+ * @param <T>
+ */
 @SuppressWarnings("unchecked")
 public class MergeableClusterInvoker<T> extends AbstractClusterInvoker<T> {
 
@@ -86,26 +87,19 @@ public class MergeableClusterInvoker<T> extends AbstractClusterInvoker<T> {
             returnType = null;
         }
 
-        Map<String, Future<Result>> results = new HashMap<String, Future<Result>>();
+        Map<String, Result> results = new HashMap<>();
         for (final Invoker<T> invoker : invokers) {
-            Future<Result> future = executor.submit(new Callable<Result>() {
-                @Override
-                public Result call() throws Exception {
-                    return invoker.invoke(new RpcInvocation(invocation, invoker));
-                }
-            });
-            results.put(invoker.getUrl().getServiceKey(), future);
+            results.put(invoker.getUrl().getServiceKey(), invoker.invoke(new RpcInvocation(invocation, invoker)));
         }
 
         Object result = null;
 
         List<Result> resultList = new ArrayList<Result>(results.size());
 
-        int timeout = getUrl().getMethodParameter(invocation.getMethodName(), Constants.TIMEOUT_KEY, Constants.DEFAULT_TIMEOUT);
-        for (Map.Entry<String, Future<Result>> entry : results.entrySet()) {
-            Future<Result> future = entry.getValue();
+        for (Map.Entry<String, Result> entry : results.entrySet()) {
+            Result asyncResult = entry.getValue();
             try {
-                Result r = future.get(timeout, TimeUnit.MILLISECONDS);
+                Result r = asyncResult.get();
                 if (r.hasException()) {
                     log.error("Invoke " + getGroupDescFromServiceKey(entry.getKey()) +
                                     " failed: " + r.getException().getMessage(),
@@ -119,13 +113,13 @@ public class MergeableClusterInvoker<T> extends AbstractClusterInvoker<T> {
         }
 
         if (resultList.isEmpty()) {
-            return new RpcResult((Object) null);
+            return AsyncRpcResult.newDefaultAsyncResult(invocation);
         } else if (resultList.size() == 1) {
             return resultList.iterator().next();
         }
 
         if (returnType == void.class) {
-            return new RpcResult((Object) null);
+            return AsyncRpcResult.newDefaultAsyncResult(invocation);
         }
 
         if (merger.startsWith(".")) {
@@ -173,7 +167,7 @@ public class MergeableClusterInvoker<T> extends AbstractClusterInvoker<T> {
                 throw new RpcException("There is no merger to merge result.");
             }
         }
-        return new RpcResult(result);
+        return AsyncRpcResult.newDefaultAsyncResult(result, invocation);
     }
 
 

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/wrapper/MockClusterInvoker.java

@@ -22,12 +22,12 @@ import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.common.utils.CollectionUtils;
 import org.apache.dubbo.common.utils.StringUtils;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 import org.apache.dubbo.rpc.support.MockInvoker;
 
@@ -113,7 +113,7 @@ public class MockClusterInvoker<T> implements Invoker<T> {
             result = minvoker.invoke(invocation);
         } catch (RpcException me) {
             if (me.isBiz()) {
-                result = new RpcResult(me.getCause());
+                result = AsyncRpcResult.newDefaultAsyncResult(me.getCause(), invocation);
             } else {
                 throw new RpcException(me.getCode(), getMockExceptionMessage(e, me), me.getCause());
             }

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/StickyTest.java

@@ -20,12 +20,12 @@ package org.apache.dubbo.rpc.cluster;
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.extension.ExtensionLoader;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.support.AbstractClusterInvoker;
 
 import org.junit.jupiter.api.Assertions;
@@ -48,7 +48,7 @@ public class StickyTest {
     private  Invoker<StickyTest> invoker2 = mock(Invoker.class);
     private RpcInvocation invocation;
     private Directory<StickyTest> dic;
-    private Result result = new RpcResult();
+    private Result result = new AppResponse();
     private StickyClusterInvoker<StickyTest> clusterinvoker = null;
     private URL url = URL.valueOf("test://test:11/test?"
                     + "&loadbalance=roundrobin"

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/directory/MockDirInvocation.java

@@ -51,6 +51,16 @@ public class MockDirInvocation implements Invocation {
         return attachments;
     }
 
+    @Override
+    public void setAttachment(String key, String value) {
+
+    }
+
+    @Override
+    public void setAttachmentIfAbsent(String key, String value) {
+
+    }
+
     public Invoker<?> getInvoker() {
         return null;
     }

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/router/file/FileRouterEngineTest.java

@@ -19,12 +19,12 @@ package org.apache.dubbo.rpc.cluster.router.file;
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.extension.ExtensionLoader;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 import org.apache.dubbo.rpc.cluster.LoadBalance;
 import org.apache.dubbo.rpc.cluster.RouterFactory;
@@ -52,7 +52,7 @@ public class FileRouterEngineTest {
     Invoker<FileRouterEngineTest> invoker2 = mock(Invoker.class);
     Invocation invocation;
     StaticDirectory<FileRouterEngineTest> dic;
-    Result result = new RpcResult();
+    Result result = new AppResponse();
     private RouterFactory routerFactory = ExtensionLoader.getExtensionLoader(RouterFactory.class).getAdaptiveExtension();
 
     @BeforeAll

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/support/FailSafeClusterInvokerTest.java

@@ -18,11 +18,11 @@ package org.apache.dubbo.rpc.cluster.support;
 
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.utils.LogUtil;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 import org.apache.dubbo.rpc.cluster.filter.DemoService;
 
@@ -48,7 +48,7 @@ public class FailSafeClusterInvokerTest {
     Invoker<DemoService> invoker = mock(Invoker.class);
     RpcInvocation invocation = new RpcInvocation();
     Directory<DemoService> dic;
-    Result result = new RpcResult();
+    Result result = new AppResponse();
 
     /**
      * @throws java.lang.Exception

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/support/FailbackClusterInvokerTest.java

@@ -20,11 +20,11 @@ package org.apache.dubbo.rpc.cluster.support;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.utils.DubboAppender;
 import org.apache.dubbo.common.utils.LogUtil;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 
 import org.apache.log4j.Level;
@@ -59,7 +59,7 @@ public class FailbackClusterInvokerTest {
     Invoker<FailbackClusterInvokerTest> invoker = mock(Invoker.class);
     RpcInvocation invocation = new RpcInvocation();
     Directory<FailbackClusterInvokerTest> dic;
-    Result result = new RpcResult();
+    Result result = new AppResponse();
 
     /**
      * @throws java.lang.Exception

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/support/FailfastClusterInvokerTest.java

@@ -17,12 +17,12 @@
 package org.apache.dubbo.rpc.cluster.support;
 
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 
 import org.junit.jupiter.api.Assertions;
@@ -47,7 +47,7 @@ public class FailfastClusterInvokerTest {
     Invoker<FailfastClusterInvokerTest> invoker1 = mock(Invoker.class);
     RpcInvocation invocation = new RpcInvocation();
     Directory<FailfastClusterInvokerTest> dic;
-    Result result = new RpcResult();
+    Result result = new AppResponse();
 
     /**
      * @throws java.lang.Exception

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/support/FailoverClusterInvokerTest.java

@@ -17,12 +17,12 @@
 package org.apache.dubbo.rpc.cluster.support;
 
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 import org.apache.dubbo.rpc.cluster.directory.StaticDirectory;
 import org.apache.dubbo.rpc.protocol.AbstractInvoker;
@@ -55,7 +55,7 @@ public class FailoverClusterInvokerTest {
     private Invoker<FailoverClusterInvokerTest> invoker2 = mock(Invoker.class);
     private RpcInvocation invocation = new RpcInvocation();
     private Directory<FailoverClusterInvokerTest> dic;
-    private Result result = new RpcResult();
+    private Result result = new AppResponse();
 
     /**
      * @throws java.lang.Exception

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/support/ForkingClusterInvokerTest.java

@@ -17,12 +17,12 @@
 package org.apache.dubbo.rpc.cluster.support;
 
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
+import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
-import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.cluster.Directory;
 
 import org.junit.jupiter.api.Assertions;
@@ -50,7 +50,7 @@ public class ForkingClusterInvokerTest {
     private Invoker<ForkingClusterInvokerTest> invoker3 = mock(Invoker.class);
     private RpcInvocation invocation = new RpcInvocation();
     private Directory<ForkingClusterInvokerTest> dic;
-    private Result result = new RpcResult();
+    private Result result = new AppResponse();
 
     @BeforeEach
     public void setUp() throws Exception {

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/support/MergeableClusterInvokerTest.java

@@ -18,10 +18,11 @@ package org.apache.dubbo.rpc.cluster.support;
 
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.rpc.AppResponse;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.cluster.Directory;
 
 import org.junit.jupiter.api.Assertions;
@@ -119,7 +120,7 @@ public class MergeableClusterInvokerTest {
                     return MenuService.class;
                 }
                 if ("invoke".equals(method.getName())) {
-                    return new RpcResult(firstMenu);
+                    return AsyncRpcResult.newDefaultAsyncResult(firstMenu, invocation);
                 }
                 return null;
             }
@@ -135,7 +136,7 @@ public class MergeableClusterInvokerTest {
                     return MenuService.class;
                 }
                 if ("invoke".equals(method.getName())) {
-                    return new RpcResult(secondMenu);
+                    return AsyncRpcResult.newDefaultAsyncResult(secondMenu, invocation);
                 }
                 return null;
             }
@@ -195,14 +196,14 @@ public class MergeableClusterInvokerTest {
         given(firstInvoker.getUrl()).willReturn(
                 url.addParameter(Constants.GROUP_KEY, "first"));
         given(firstInvoker.getInterface()).willReturn(MenuService.class);
-        given(firstInvoker.invoke(invocation)).willReturn(new RpcResult())
+        given(firstInvoker.invoke(invocation)).willReturn(new AppResponse())
                 ;
         given(firstInvoker.isAvailable()).willReturn(true);
 
         given(secondInvoker.getUrl()).willReturn(
                 url.addParameter(Constants.GROUP_KEY, "second"));
         given(secondInvoker.getInterface()).willReturn(MenuService.class);
-        given(secondInvoker.invoke(invocation)).willReturn(new RpcResult())
+        given(secondInvoker.invoke(invocation)).willReturn(new AppResponse())
                 ;
         given(secondInvoker.isAvailable()).willReturn(true);
 

dubbo-common/src/main/java/org/apache/dubbo/common/Constants.java

@@ -91,6 +91,8 @@ public class Constants {
 
     public static final String $INVOKE = "$invoke";
 
+    public static final String $INVOKE_ASYNC = "$invokeAsync";
+
     public static final String $ECHO = "$echo";
 
     public static final int DEFAULT_IO_THREADS = Math.min(Runtime.getRuntime().availableProcessors() + 1, 32);
@@ -827,16 +829,16 @@ public class Constants {
      */
     public static final String DEVELOPMENT_ENVIRONMENT = "develop";
 
-    /**
-     * Production environment key.
-     */
-    public static final String PRODUCTION_ENVIRONMENT = "product";
-
     /**
      * Consumer side 's proxy class
      */
     public static final String PROXY_CLASS_REF = "refClass";
 
+    /**
+     * Production environment key.
+     */
+    public static final String PRODUCTION_ENVIRONMENT = "product";
+
     public static final String ETCD3_NOTIFY_MAXTHREADS_KEYS = "etcd3.notify.maxthreads";
 
     public static final int DEFAULT_ETCD3_NOTIFY_THREADS = DEFAULT_IO_THREADS;

dubbo-common/src/main/java/org/apache/dubbo/common/logger/Logger.java

@@ -142,7 +142,7 @@ public interface Logger {
 
     /**
      * Is debug logging currently enabled?
-     *
+     * 
      * @return true if debug is enabled
      */
     boolean isDebugEnabled();

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

@@ -28,6 +28,7 @@ import java.lang.reflect.GenericArrayType;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
 import java.net.URL;
 import java.security.CodeSource;
 import java.security.ProtectionDomain;
@@ -39,6 +40,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.Future;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -1096,4 +1098,25 @@ public final class ReflectUtils {
 
         return properties;
     }
+
+    public static Type[] getReturnTypes(Method method) {
+        Class<?> returnType = method.getReturnType();
+        Type genericReturnType = method.getGenericReturnType();
+        if (Future.class.isAssignableFrom(returnType)) {
+            if (genericReturnType instanceof ParameterizedType) {
+                Type actualArgType = ((ParameterizedType) genericReturnType).getActualTypeArguments()[0];
+                if (actualArgType instanceof ParameterizedType) {
+                    returnType = (Class<?>) ((ParameterizedType) actualArgType).getRawType();
+                    genericReturnType = actualArgType;
+                } else {
+                    returnType = (Class<?>) actualArgType;
+                    genericReturnType = returnType;
+                }
+            } else {
+                returnType = null;
+                genericReturnType = null;
+            }
+        }
+        return new Type[]{returnType, genericReturnType};
+    }
 }

dubbo-common/src/test/java/org/apache/dubbo/common/config/PropertiesConfigurationTest.java

@@ -16,6 +16,7 @@
  */
 package org.apache.dubbo.common.config;
 
+
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 

dubbo-compatible/src/main/java/com/alibaba/dubbo/rpc/Invocation.java

@@ -29,6 +29,15 @@ public interface Invocation extends org.apache.dubbo.rpc.Invocation {
         return null;
     }
 
+    @Override
+    default void setAttachmentIfAbsent(String key, String value) {
+    }
+
+    @Override
+    default void setAttachment(String key, String value) {
+
+    }
+
     class CompatibleInvocation implements Invocation {
 
         private org.apache.dubbo.rpc.Invocation delegate;

dubbo-compatible/src/main/java/com/alibaba/dubbo/rpc/Result.java

@@ -17,11 +17,42 @@
 
 package com.alibaba.dubbo.rpc;
 
+import org.apache.dubbo.rpc.AppResponse;
+
 import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.function.Function;
 
 @Deprecated
 public interface Result extends org.apache.dubbo.rpc.Result {
 
+    @Override
+    default void setValue(Object value) {
+
+    }
+
+    @Override
+    default void setException(Throwable t) {
+
+    }
+
+    @Override
+    default org.apache.dubbo.rpc.Result thenApplyWithContext(Function<AppResponse, AppResponse> fn) {
+        return this;
+    }
+
+    @Override
+    default <U> CompletableFuture<U> thenApply(Function<org.apache.dubbo.rpc.Result, ? extends U> fn) {
+        return null;
+    }
+
+    @Override
+    default org.apache.dubbo.rpc.Result get() throws InterruptedException, ExecutionException {
+        return this;
+    }
+
+
     class CompatibleResult implements Result {
         private org.apache.dubbo.rpc.Result delegate;
 
@@ -53,11 +84,6 @@ public interface Result extends org.apache.dubbo.rpc.Result {
             return delegate.recreate();
         }
 
-        @Override
-        public Object getResult() {
-            return delegate.getResult();
-        }
-
         @Override
         public Map<String, String> getAttachments() {
             return delegate.getAttachments();

dubbo-compatible/src/test/java/org/apache/dubbo/filter/LegacyInvoker.java

@@ -17,7 +17,7 @@
 package org.apache.dubbo.filter;
 
 
-import org.apache.dubbo.rpc.RpcResult;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.service.DemoService;
 
 import com.alibaba.dubbo.common.URL;
@@ -58,7 +58,7 @@ public class LegacyInvoker<T> implements Invoker<T> {
     }
 
     public Result invoke(Invocation invocation) throws RpcException {
-        RpcResult result = new RpcResult();
+        AppResponse result = new AppResponse();
         if (hasException == false) {
             result.setValue("alibaba");
         } else {

dubbo-compatible/src/test/java/org/apache/dubbo/service/MockInvocation.java

@@ -57,6 +57,16 @@ public class MockInvocation implements Invocation {
         return attachments;
     }
 
+    @Override
+    public void setAttachment(String key, String value) {
+
+    }
+
+    @Override
+    public void setAttachmentIfAbsent(String key, String value) {
+
+    }
+
     public Invoker<?> getInvoker() {
         return null;
     }

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ReferenceConfig.java

@@ -265,7 +265,7 @@ public class ReferenceConfig<T> extends AbstractReferenceConfig {
         checkStubAndLocal(interfaceClass);
         checkMock(interfaceClass);
 
-        ConsumerModel consumerModel = new ConsumerModel(interfaceName, group, version, interfaceClass);
+        ConsumerModel consumerModel = new ConsumerModel(interfaceName, group, version, getActualInterface());
         ApplicationModel.initConsumerModel(URL.buildKey(interfaceName, group, version), consumerModel);
 
         Map<String, String> map = new HashMap<String, String>();
@@ -321,6 +321,17 @@ public class ReferenceConfig<T> extends AbstractReferenceConfig {
         consumerModel.getServiceMetadata().addAttribute(Constants.PROXY_CLASS_REF, ref);
     }
 
+    private Class<?> getActualInterface() {
+        Class actualInterface = interfaceClass;
+        if (interfaceClass == GenericService.class) {
+            try {
+                actualInterface = Class.forName(interfaceName);
+            } catch (ClassNotFoundException e) {
+                // ignore
+            }
+        }
+        return actualInterface;
+    }
     @SuppressWarnings({"unchecked", "rawtypes", "deprecation"})
     private T createProxy(Map<String, String> map) {
         if (shouldJvmRefer(map)) {

dubbo-configcenter/dubbo-configcenter-zookeeper/src/main/java/org/apache/dubbo/configcenter/support/zookeeper/CacheListener.java

@@ -35,6 +35,8 @@ import java.util.concurrent.CountDownLatch;
  */
 
 public class CacheListener implements DataListener {
+    private static final int MIN_PATH_DEPTH = 5;
+
     private Map<String, Set<ConfigurationListener>> keyListeners = new ConcurrentHashMap<>();
     private CountDownLatch initializedLatch;
     private String rootPath;
@@ -89,7 +91,7 @@ public class CacheListener implements DataListener {
         // TODO We limit the notification of config changes to a specific path level, for example
         //  /dubbo/config/service/configurators, other config changes not in this level will not get notified,
         //  say /dubbo/config/dubbo.properties
-        if (path.split("/").length >= 5) {
+        if (path.split("/").length >= MIN_PATH_DEPTH) {
             String key = pathToKey(path);
             ConfigChangeType changeType;
             switch (eventType) {

dubbo-demo/dubbo-demo-annotation/dubbo-demo-annotation-consumer/src/main/java/org/apache/dubbo/demo/consumer/comp/DemoServiceComponent.java

@@ -24,6 +24,8 @@ import org.apache.dubbo.demo.DemoService;
 
 import org.springframework.stereotype.Component;
 
+import java.util.concurrent.CompletableFuture;
+
 @Component("demoServiceComponent")
 public class DemoServiceComponent implements DemoService {
     @Reference
@@ -33,4 +35,9 @@ public class DemoServiceComponent implements DemoService {
     public String sayHello(String name) {
         return demoService.sayHello(name);
     }
+
+    @Override
+    public CompletableFuture<String> sayHelloAsync(String name) {
+        return null;
+    }
 }

dubbo-demo/dubbo-demo-annotation/dubbo-demo-annotation-provider/src/main/java/org/apache/dubbo/demo/provider/DemoServiceImpl.java

@@ -25,6 +25,8 @@ import org.apache.dubbo.rpc.RpcContext;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.concurrent.CompletableFuture;
+
 @Service
 public class DemoServiceImpl implements DemoService {
     private static final Logger logger = LoggerFactory.getLogger(DemoServiceImpl.class);
@@ -35,4 +37,9 @@ public class DemoServiceImpl implements DemoService {
         return "Hello " + name + ", response from provider: " + RpcContext.getContext().getLocalAddress();
     }
 
+    @Override
+    public CompletableFuture<String> sayHelloAsync(String name) {
+        return null;
+    }
+
 }

dubbo-demo/dubbo-demo-api/dubbo-demo-api-provider/src/main/java/org/apache/dubbo/demo/provider/DemoServiceImpl.java

@@ -22,6 +22,8 @@ import org.apache.dubbo.rpc.RpcContext;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.concurrent.CompletableFuture;
+
 public class DemoServiceImpl implements DemoService {
     private static final Logger logger = LoggerFactory.getLogger(DemoServiceImpl.class);
 
@@ -31,4 +33,9 @@ public class DemoServiceImpl implements DemoService {
         return "Hello " + name + ", response from provider: " + RpcContext.getContext().getLocalAddress();
     }
 
+    @Override
+    public CompletableFuture<String> sayHelloAsync(String name) {
+        return null;
+    }
+
 }

dubbo-demo/dubbo-demo-interface/src/main/java/org/apache/dubbo/demo/DemoService.java

@@ -16,8 +16,11 @@
  */
 package org.apache.dubbo.demo;
 
+import java.util.concurrent.CompletableFuture;
+
 public interface DemoService {
 
     String sayHello(String name);
 
+    CompletableFuture<String> sayHelloAsync(String name);
 }

dubbo-demo/dubbo-demo-xml/dubbo-demo-xml-consumer/src/main/java/org/apache/dubbo/demo/consumer/Application.java

@@ -20,16 +20,21 @@ import org.apache.dubbo.demo.DemoService;
 
 import org.springframework.context.support.ClassPathXmlApplicationContext;
 
+import java.util.concurrent.CompletableFuture;
+
 public class Application {
     /**
      * In order to make sure multicast registry works, need to specify '-Djava.net.preferIPv4Stack=true' before
      * launch the application
      */
-    public static void main(String[] args) {
+    public static void main(String[] args) throws Exception {
         ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring/dubbo-consumer.xml");
         context.start();
         DemoService demoService = context.getBean("demoService", DemoService.class);
-        String hello = demoService.sayHello("world");
-        System.out.println("result: " + hello);
+//        String hello = demoService.sayHello("world");
+        CompletableFuture<String> helloFuture = demoService.sayHelloAsync("world");
+//        System.out.println("result: " + hello);
+        System.out.println("result: " + helloFuture.get());
+        System.in.read();
     }
 }

dubbo-demo/dubbo-demo-xml/dubbo-demo-xml-consumer/src/main/resources/spring/dubbo-consumer.xml

@@ -27,6 +27,6 @@
 
     <!-- generate proxy for the remote service, then demoService can be used in the same way as the
     local regular interface -->
-    <dubbo:reference id="demoService" check="false" interface="org.apache.dubbo.demo.DemoService"/>
+    <dubbo:reference timeout="600000" id="demoService" check="false" interface="org.apache.dubbo.demo.DemoService"/>
 
 </beans>

dubbo-demo/dubbo-demo-xml/dubbo-demo-xml-provider/src/main/java/org/apache/dubbo/demo/provider/DemoServiceImpl.java

@@ -22,6 +22,8 @@ import org.apache.dubbo.rpc.RpcContext;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.concurrent.CompletableFuture;
+
 public class DemoServiceImpl implements DemoService {
     private static final Logger logger = LoggerFactory.getLogger(DemoServiceImpl.class);
 
@@ -31,4 +33,14 @@ public class DemoServiceImpl implements DemoService {
         return "Hello " + name + ", response from provider: " + RpcContext.getContext().getLocalAddress();
     }
 
+    @Override
+    public CompletableFuture<String> sayHelloAsync(String name) {
+        try {
+            Thread.sleep(10000);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+        return CompletableFuture.completedFuture("future return value!");
+    }
+
 }

dubbo-filter/dubbo-filter-cache/src/main/java/org/apache/dubbo/cache/filter/CacheFilter.java

@@ -22,12 +22,12 @@ import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.extension.Activate;
 import org.apache.dubbo.common.utils.ConfigUtils;
 import org.apache.dubbo.common.utils.StringUtils;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
-import org.apache.dubbo.rpc.RpcResult;
 
 import java.io.Serializable;
 
@@ -95,9 +95,9 @@ public class CacheFilter implements Filter {
                 Object value = cache.get(key);
                 if (value != null) {
                     if (value instanceof ValueWrapper) {
-                        return new RpcResult(((ValueWrapper)value).get());
+                        return AsyncRpcResult.newDefaultAsyncResult(((ValueWrapper) value).get(), invocation);
                     } else {
-                        return new RpcResult(value);
+                        return AsyncRpcResult.newDefaultAsyncResult(value, invocation);
                     }
                 }
                 Result result = invoker.invoke(invocation);

dubbo-filter/dubbo-filter-cache/src/test/java/org/apache/dubbo/cache/filter/CacheFilterTest.java

@@ -22,9 +22,10 @@ import org.apache.dubbo.cache.support.jcache.JCacheFactory;
 import org.apache.dubbo.cache.support.lru.LruCacheFactory;
 import org.apache.dubbo.cache.support.threadlocal.ThreadLocalCacheFactory;
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.params.ParameterizedTest;
@@ -60,19 +61,19 @@ public class CacheFilterTest {
 
         URL url = URL.valueOf("test://test:11/test?cache=" + cacheType);
 
-        given(invoker.invoke(invocation)).willReturn(new RpcResult("value"));
+        given(invoker.invoke(invocation)).willReturn(AsyncRpcResult.newDefaultAsyncResult("value", invocation));
         given(invoker.getUrl()).willReturn(url);
 
-        given(invoker1.invoke(invocation)).willReturn(new RpcResult("value1"));
+        given(invoker1.invoke(invocation)).willReturn(AsyncRpcResult.newDefaultAsyncResult("value1", invocation));
         given(invoker1.getUrl()).willReturn(url);
 
-        given(invoker2.invoke(invocation)).willReturn(new RpcResult("value2"));
+        given(invoker2.invoke(invocation)).willReturn(AsyncRpcResult.newDefaultAsyncResult("value2", invocation));
         given(invoker2.getUrl()).willReturn(url);
 
-        given(invoker3.invoke(invocation)).willReturn(new RpcResult(new RuntimeException()));
+        given(invoker3.invoke(invocation)).willReturn(AsyncRpcResult.newDefaultAsyncResult(new RuntimeException(), invocation));
         given(invoker3.getUrl()).willReturn(url);
 
-        given(invoker4.invoke(invocation)).willReturn(new RpcResult());
+        given(invoker4.invoke(invocation)).willReturn(AsyncRpcResult.newDefaultAsyncResult(invocation));
         given(invoker4.getUrl()).willReturn(url);
     }
 
@@ -85,8 +86,8 @@ public class CacheFilterTest {
         invocation.setArguments(new Object[]{});
 
         cacheFilter.invoke(invoker, invocation);
-        RpcResult rpcResult1 = (RpcResult) cacheFilter.invoke(invoker1, invocation);
-        RpcResult rpcResult2 = (RpcResult) cacheFilter.invoke(invoker2, invocation);
+        Result rpcResult1 = cacheFilter.invoke(invoker1, invocation);
+        Result rpcResult2 = cacheFilter.invoke(invoker2, invocation);
         Assertions.assertEquals(rpcResult1.getValue(), rpcResult2.getValue());
         Assertions.assertEquals(rpcResult1.getValue(), "value");
     }
@@ -100,8 +101,8 @@ public class CacheFilterTest {
         invocation.setArguments(new Object[]{"arg1"});
 
         cacheFilter.invoke(invoker, invocation);
-        RpcResult rpcResult1 = (RpcResult) cacheFilter.invoke(invoker1, invocation);
-        RpcResult rpcResult2 = (RpcResult) cacheFilter.invoke(invoker2, invocation);
+        Result rpcResult1 = cacheFilter.invoke(invoker1, invocation);
+        Result rpcResult2 = cacheFilter.invoke(invoker2, invocation);
         Assertions.assertEquals(rpcResult1.getValue(), rpcResult2.getValue());
         Assertions.assertEquals(rpcResult1.getValue(), "value");
     }
@@ -115,7 +116,7 @@ public class CacheFilterTest {
         invocation.setArguments(new Object[]{"arg2"});
 
         cacheFilter.invoke(invoker3, invocation);
-        RpcResult rpcResult = (RpcResult) cacheFilter.invoke(invoker2, invocation);
+        Result rpcResult = cacheFilter.invoke(invoker2, invocation);
         Assertions.assertEquals(rpcResult.getValue(), "value2");
     }
 
@@ -128,9 +129,9 @@ public class CacheFilterTest {
         invocation.setArguments(new Object[]{"arg3"});
 
         cacheFilter.invoke(invoker4, invocation);
-        RpcResult rpcResult1 = (RpcResult) cacheFilter.invoke(invoker1, invocation);
-        RpcResult rpcResult2 = (RpcResult) cacheFilter.invoke(invoker2, invocation);
-        Assertions.assertEquals(rpcResult1.getValue(), null);
-        Assertions.assertEquals(rpcResult2.getValue(), null);
+        Result result1 = cacheFilter.invoke(invoker1, invocation);
+        Result result2 = cacheFilter.invoke(invoker2, invocation);
+        Assertions.assertEquals(result1.getValue(), null);
+        Assertions.assertEquals(result2.getValue(), null);
     }
 }

dubbo-filter/dubbo-filter-validation/src/main/java/org/apache/dubbo/validation/filter/ValidationFilter.java

@@ -19,12 +19,12 @@ package org.apache.dubbo.validation.filter;
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.extension.Activate;
 import org.apache.dubbo.common.utils.ConfigUtils;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.validation.Validation;
 import org.apache.dubbo.validation.Validator;
 
@@ -87,7 +87,7 @@ public class ValidationFilter implements Filter {
             } catch (RpcException e) {
                 throw e;
             } catch (Throwable t) {
-                return new RpcResult(t);
+                return AsyncRpcResult.newDefaultAsyncResult(t, invocation);
             }
         }
         return invoker.invoke(invocation);

dubbo-filter/dubbo-filter-validation/src/main/java/org/apache/dubbo/validation/support/jvalidation/JValidator.java

@@ -94,7 +94,7 @@ public class JValidator implements Validator {
             factory = Validation.buildDefaultValidatorFactory();
         }
         this.validator = factory.getValidator();
-        this.methodClassMap = new ConcurrentHashMap<String, Class>();
+        this.methodClassMap = new ConcurrentHashMap<>();
     }
 
     private static boolean isPrimitives(Class<?> cls) {
@@ -117,7 +117,7 @@ public class JValidator implements Validator {
             String parameterClassName = generateMethodParameterClassName(clazz, method);
             Class<?> parameterClass;
             try {
-                parameterClass = (Class<?>) Class.forName(parameterClassName, true, clazz.getClassLoader());
+                parameterClass = Class.forName(parameterClassName, true, clazz.getClassLoader());
             } catch (ClassNotFoundException e) {
                 ClassPool pool = ClassGenerator.getClassPool(clazz.getClassLoader());
                 CtClass ctClass = pool.makeClass(parameterClassName);
@@ -243,14 +243,14 @@ public class JValidator implements Validator {
 
     @Override
     public void validate(String methodName, Class<?>[] parameterTypes, Object[] arguments) throws Exception {
-        List<Class<?>> groups = new ArrayList<Class<?>>();
+        List<Class<?>> groups = new ArrayList<>();
         Class<?> methodClass = methodClass(methodName);
         if (methodClass != null) {
             groups.add(methodClass);
         }
-        Set<ConstraintViolation<?>> violations = new HashSet<ConstraintViolation<?>>();
+        Set<ConstraintViolation<?>> violations = new HashSet<>();
         Method method = clazz.getMethod(methodName, parameterTypes);
-        Class<?>[] methodClasses = null;
+        Class<?>[] methodClasses;
         if (method.isAnnotationPresent(MethodValidated.class)){
             methodClasses = method.getAnnotation(MethodValidated.class).value();
             groups.addAll(Arrays.asList(methodClasses));
@@ -260,7 +260,7 @@ public class JValidator implements Validator {
         groups.add(1, clazz);
 
         // convert list to array
-        Class<?>[] classgroups = groups.toArray(new Class[0]);
+        Class<?>[] classgroups = groups.toArray(new Class[groups.size()]);
 
         Object parameterBean = getMethodParameterBean(clazz, method, arguments);
         if (parameterBean != null) {

dubbo-filter/dubbo-filter-validation/src/test/java/org/apache/dubbo/validation/filter/ValidationFilterTest.java

@@ -17,11 +17,11 @@
 package org.apache.dubbo.validation.filter;
 
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.validation.Validation;
 import org.apache.dubbo.validation.Validator;
 
@@ -52,7 +52,7 @@ public class ValidationFilterTest {
         URL url = URL.valueOf("test://test:11/test?default.validation=true");
 
         given(validation.getValidator(url)).willThrow(new IllegalStateException("Not found class test, cause: test"));
-        given(invoker.invoke(invocation)).willReturn(new RpcResult("success"));
+        given(invoker.invoke(invocation)).willReturn(new AppResponse("success"));
         given(invoker.getUrl()).willReturn(url);
         given(invocation.getMethodName()).willReturn("echo1");
         given(invocation.getParameterTypes()).willReturn(new Class<?>[]{String.class});
@@ -70,7 +70,7 @@ public class ValidationFilterTest {
         URL url = URL.valueOf("test://test:11/test?default.validation=true");
 
         given(validation.getValidator(url)).willReturn(validator);
-        given(invoker.invoke(invocation)).willReturn(new RpcResult("success"));
+        given(invoker.invoke(invocation)).willReturn(new AppResponse("success"));
         given(invoker.getUrl()).willReturn(url);
         given(invocation.getMethodName()).willReturn("echo1");
         given(invocation.getParameterTypes()).willReturn(new Class<?>[]{String.class});
@@ -87,7 +87,7 @@ public class ValidationFilterTest {
         URL url = URL.valueOf("test://test:11/test");
 
         given(validation.getValidator(url)).willReturn(validator);
-        given(invoker.invoke(invocation)).willReturn(new RpcResult("success"));
+        given(invoker.invoke(invocation)).willReturn(new AppResponse("success"));
         given(invoker.getUrl()).willReturn(url);
         given(invocation.getMethodName()).willReturn("echo1");
         given(invocation.getParameterTypes()).willReturn(new Class<?>[]{String.class});
@@ -104,7 +104,7 @@ public class ValidationFilterTest {
         URL url = URL.valueOf("test://test:11/test");
 
         given(validation.getValidator(url)).willReturn(validator);
-        given(invoker.invoke(invocation)).willReturn(new RpcResult("success"));
+        given(invoker.invoke(invocation)).willReturn(new AppResponse("success"));
         given(invoker.getUrl()).willReturn(url);
         given(invocation.getMethodName()).willReturn("$echo1");
         given(invocation.getParameterTypes()).willReturn(new Class<?>[]{String.class});
@@ -124,7 +124,7 @@ public class ValidationFilterTest {
             URL url = URL.valueOf("test://test:11/test?default.validation=true");
 
             given(validation.getValidator(url)).willThrow(new RpcException("rpc exception"));
-            given(invoker.invoke(invocation)).willReturn(new RpcResult("success"));
+            given(invoker.invoke(invocation)).willReturn(new AppResponse("success"));
             given(invoker.getUrl()).willReturn(url);
             given(invocation.getMethodName()).willReturn("echo1");
             given(invocation.getParameterTypes()).willReturn(new Class<?>[]{String.class});

dubbo-filter/dubbo-filter-validation/src/test/java/org/apache/dubbo/validation/support/jvalidation/JValidatorTest.java

@@ -23,6 +23,10 @@ import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 import javax.validation.ConstraintViolationException;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 
 public class JValidatorTest {
     @Test
@@ -56,4 +60,27 @@ public class JValidatorTest {
         JValidator jValidator = new JValidator(url);
         jValidator.validate("someMethod2", new Class<?>[]{ValidationParameter.class}, new Object[]{new ValidationParameter("NotBeNull")});
     }
+
+    @Test
+    public void testItWithArrayArg() throws Exception {
+        URL url = URL.valueOf("test://test:11/org.apache.dubbo.validation.support.jvalidation.mock.JValidatorTestTarget");
+        JValidator jValidator = new JValidator(url);
+        jValidator.validate("someMethod3", new Class<?>[]{ValidationParameter[].class}, new Object[]{new ValidationParameter[]{new ValidationParameter("parameter")}});
+    }
+
+    @Test
+    public void testItWithCollectionArg() throws Exception {
+        URL url = URL.valueOf("test://test:11/org.apache.dubbo.validation.support.jvalidation.mock.JValidatorTestTarget");
+        JValidator jValidator = new JValidator(url);
+        jValidator.validate("someMethod4", new Class<?>[]{List.class}, new Object[]{Arrays.asList("parameter")});
+    }
+
+    @Test
+    public void testItWithMapArg() throws Exception {
+        URL url = URL.valueOf("test://test:11/org.apache.dubbo.validation.support.jvalidation.mock.JValidatorTestTarget");
+        JValidator jValidator = new JValidator(url);
+        Map<String, String> map = new HashMap<>();
+        map.put("key", "value");
+        jValidator.validate("someMethod5", new Class<?>[]{Map.class}, new Object[]{map});
+    }
 }

dubbo-filter/dubbo-filter-validation/src/test/java/org/apache/dubbo/validation/support/jvalidation/mock/JValidatorTestTarget.java

@@ -19,6 +19,8 @@ package org.apache.dubbo.validation.support.jvalidation.mock;
 import org.apache.dubbo.validation.MethodValidated;
 
 import javax.validation.constraints.NotNull;
+import java.util.List;
+import java.util.Map;
 
 public interface JValidatorTestTarget {
     @MethodValidated
@@ -27,6 +29,12 @@ public interface JValidatorTestTarget {
     @MethodValidated(Test2.class)
     public void someMethod2(@NotNull ValidationParameter validationParameter);
 
+    public void someMethod3(ValidationParameter[] parameters);
+
+    public void someMethod4(List<String> strings);
+
+    public void someMethod5(Map<String, String> map);
+
     @interface Test2 {
     }
 

dubbo-monitor/dubbo-monitor-api/src/main/java/org/apache/dubbo/monitor/MonitorService.java

@@ -86,4 +86,5 @@ public interface MonitorService {
      */
     List<URL> lookup(URL query);
 
+
 }

dubbo-monitor/dubbo-monitor-api/src/main/java/org/apache/dubbo/monitor/support/MonitorFilter.java

@@ -25,9 +25,9 @@ import org.apache.dubbo.common.utils.NetUtils;
 import org.apache.dubbo.monitor.Monitor;
 import org.apache.dubbo.monitor.MonitorFactory;
 import org.apache.dubbo.monitor.MonitorService;
-import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
@@ -41,10 +41,14 @@ import java.util.concurrent.atomic.AtomicInteger;
  * MonitorFilter. (SPI, Singleton, ThreadSafe)
  */
 @Activate(group = {Constants.PROVIDER, Constants.CONSUMER})
-public class MonitorFilter implements Filter {
+public class MonitorFilter extends ListenableFilter {
 
     private static final Logger logger = LoggerFactory.getLogger(MonitorFilter.class);
+    private static final String MONITOR_FILTER_START_TIME = "monitor_filter_start_time";
 
+    public MonitorFilter() {
+        super.listener = new MonitorListener();
+    }
     /**
      * The Concurrent counter
      */
@@ -59,6 +63,7 @@ public class MonitorFilter implements Filter {
         this.monitorFactory = monitorFactory;
     }
 
+
     /**
      * The invocation interceptor,it will collect the invoke data about this invocation and send it to monitor center
      *
@@ -70,105 +75,10 @@ public class MonitorFilter implements Filter {
     @Override
     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
         if (invoker.getUrl().hasParameter(Constants.MONITOR_KEY)) {
-            RpcContext context = RpcContext.getContext(); // provider must fetch context before invoke() gets called
-            String remoteHost = context.getRemoteHost();
-            long start = System.currentTimeMillis(); // record start timestamp
+            invocation.setAttachment(MONITOR_FILTER_START_TIME, String.valueOf(System.currentTimeMillis()));
             getConcurrent(invoker, invocation).incrementAndGet(); // count up
-            try {
-                Result result = invoker.invoke(invocation); // proceed invocation chain
-                collect(invoker, invocation, result, remoteHost, start, false);
-                return result;
-            } catch (RpcException e) {
-                collect(invoker, invocation, null, remoteHost, start, true);
-                throw e;
-            } finally {
-                getConcurrent(invoker, invocation).decrementAndGet(); // count down
-            }
-        } else {
-            return invoker.invoke(invocation);
         }
-    }
-
-    /**
-     * The collector logic, it will be handled by the default monitor
-     *
-     * @param invoker
-     * @param invocation
-     * @param result     the invoke result
-     * @param remoteHost the remote host address
-     * @param start      the timestamp the invoke begin
-     * @param error      if there is an error on the invoke
-     */
-    private void collect(Invoker<?> invoker, Invocation invocation, Result result, String remoteHost, long start, boolean error) {
-        try {
-            URL monitorUrl = invoker.getUrl().getUrlParameter(Constants.MONITOR_KEY);
-            Monitor monitor = monitorFactory.getMonitor(monitorUrl);
-            if (monitor == null) {
-                return;
-            }
-            URL statisticsURL = createStatisticsUrl(invoker, invocation, result, remoteHost, start, error);
-            monitor.collect(statisticsURL);
-        } catch (Throwable t) {
-            logger.warn("Failed to monitor count service " + invoker.getUrl() + ", cause: " + t.getMessage(), t);
-        }
-    }
-
-    /**
-     * Create statistics url
-     *
-     * @param invoker
-     * @param invocation
-     * @param result
-     * @param remoteHost
-     * @param start
-     * @param error
-     * @return
-     */
-    private URL createStatisticsUrl(Invoker<?> invoker, Invocation invocation, Result result, String remoteHost, long start, boolean error) {
-        // ---- service statistics ----
-        long elapsed = System.currentTimeMillis() - start; // invocation cost
-        int concurrent = getConcurrent(invoker, invocation).get(); // current concurrent count
-        String application = invoker.getUrl().getParameter(Constants.APPLICATION_KEY);
-        String service = invoker.getInterface().getName(); // service name
-        String method = RpcUtils.getMethodName(invocation); // method name
-        String group = invoker.getUrl().getParameter(Constants.GROUP_KEY);
-        String version = invoker.getUrl().getParameter(Constants.VERSION_KEY);
-
-        int localPort;
-        String remoteKey, remoteValue;
-        if (Constants.CONSUMER_SIDE.equals(invoker.getUrl().getParameter(Constants.SIDE_KEY))) {
-            // ---- for service consumer ----
-            localPort = 0;
-            remoteKey = MonitorService.PROVIDER;
-            remoteValue = invoker.getUrl().getAddress();
-        } else {
-            // ---- for service provider ----
-            localPort = invoker.getUrl().getPort();
-            remoteKey = MonitorService.CONSUMER;
-            remoteValue = remoteHost;
-        }
-        String input = "", output = "";
-        if (invocation.getAttachment(Constants.INPUT_KEY) != null) {
-            input = invocation.getAttachment(Constants.INPUT_KEY);
-        }
-        if (result != null && result.getAttachment(Constants.OUTPUT_KEY) != null) {
-            output = result.getAttachment(Constants.OUTPUT_KEY);
-        }
-
-        return new URL(Constants.COUNT_PROTOCOL,
-                NetUtils.getLocalHost(), localPort,
-                service + Constants.PATH_SEPARATOR + method,
-                MonitorService.APPLICATION, application,
-                MonitorService.INTERFACE, service,
-                MonitorService.METHOD, method,
-                remoteKey, remoteValue,
-                error ? MonitorService.FAILURE : MonitorService.SUCCESS, "1",
-                MonitorService.ELAPSED, String.valueOf(elapsed),
-                MonitorService.CONCURRENT, String.valueOf(concurrent),
-                Constants.INPUT_KEY, input,
-                Constants.OUTPUT_KEY, output,
-                Constants.GROUP_KEY, group,
-                Constants.VERSION_KEY, version);
+        return invoker.invoke(invocation); // proceed invocation chain
     }
 
     // concurrent counter
@@ -182,4 +92,93 @@ public class MonitorFilter implements Filter {
         return concurrent;
     }
 
+    class MonitorListener implements Listener {
+
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
+            if (invoker.getUrl().hasParameter(Constants.MONITOR_KEY)) {
+                collect(invoker, invocation, result, RpcContext.getContext().getRemoteHost(), Long.valueOf(invocation.getAttachment(MONITOR_FILTER_START_TIME)), false);
+                getConcurrent(invoker, invocation).decrementAndGet(); // count down
+            }
+        }
+
+        @Override
+        public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
+            if (invoker.getUrl().hasParameter(Constants.MONITOR_KEY)) {
+                collect(invoker, invocation, null, RpcContext.getContext().getRemoteHost(), Long.valueOf(invocation.getAttachment(MONITOR_FILTER_START_TIME)), true);
+                getConcurrent(invoker, invocation).decrementAndGet(); // count down
+            }
+        }
+
+        /**
+         * The collector logic, it will be handled by the default monitor
+         *
+         * @param invoker
+         * @param invocation
+         * @param result     the invoke result
+         * @param remoteHost the remote host address
+         * @param start      the timestamp the invoke begin
+         * @param error      if there is an error on the invoke
+         */
+        private void collect(Invoker<?> invoker, Invocation invocation, Result result, String remoteHost, long start, boolean error) {
+            try {
+                URL monitorUrl = invoker.getUrl().getUrlParameter(Constants.MONITOR_KEY);
+                Monitor monitor = monitorFactory.getMonitor(monitorUrl);
+                if (monitor == null) {
+                    return;
+                }
+                URL statisticsURL = createStatisticsUrl(invoker, invocation, result, remoteHost, start, error);
+                monitor.collect(statisticsURL);
+            } catch (Throwable t) {
+                logger.warn("Failed to monitor count service " + invoker.getUrl() + ", cause: " + t.getMessage(), t);
+            }
+        }
+
+        /**
+         * Create statistics url
+         *
+         * @param invoker
+         * @param invocation
+         * @param result
+         * @param remoteHost
+         * @param start
+         * @param error
+         * @return
+         */
+        private URL createStatisticsUrl(Invoker<?> invoker, Invocation invocation, Result result, String remoteHost, long start, boolean error) {
+            // ---- service statistics ----
+            long elapsed = System.currentTimeMillis() - start; // invocation cost
+            int concurrent = getConcurrent(invoker, invocation).get(); // current concurrent count
+            String application = invoker.getUrl().getParameter(Constants.APPLICATION_KEY);
+            String service = invoker.getInterface().getName(); // service name
+            String method = RpcUtils.getMethodName(invocation); // method name
+            String group = invoker.getUrl().getParameter(Constants.GROUP_KEY);
+            String version = invoker.getUrl().getParameter(Constants.VERSION_KEY);
+
+            int localPort;
+            String remoteKey, remoteValue;
+            if (Constants.CONSUMER_SIDE.equals(invoker.getUrl().getParameter(Constants.SIDE_KEY))) {
+                // ---- for service consumer ----
+                localPort = 0;
+                remoteKey = MonitorService.PROVIDER;
+                remoteValue = invoker.getUrl().getAddress();
+            } else {
+                // ---- for service provider ----
+                localPort = invoker.getUrl().getPort();
+                remoteKey = MonitorService.CONSUMER;
+                remoteValue = remoteHost;
+            }
+            String input = "", output = "";
+            if (invocation.getAttachment(Constants.INPUT_KEY) != null) {
+                input = invocation.getAttachment(Constants.INPUT_KEY);
+            }
+            if (result != null && result.getAttachment(Constants.OUTPUT_KEY) != null) {
+                output = result.getAttachment(Constants.OUTPUT_KEY);
+            }
+
+            return new URL(Constants.COUNT_PROTOCOL, NetUtils.getLocalHost(), localPort, service + Constants.PATH_SEPARATOR + method, MonitorService.APPLICATION, application, MonitorService.INTERFACE, service, MonitorService.METHOD, method, remoteKey, remoteValue, error ? MonitorService.FAILURE : MonitorService.SUCCESS, "1", MonitorService.ELAPSED, String.valueOf(elapsed), MonitorService.CONCURRENT, String.valueOf(concurrent), Constants.INPUT_KEY, input, Constants.OUTPUT_KEY, output, Constants.GROUP_KEY, group, Constants.VERSION_KEY, version);
+        }
+
+    }
+
 }

dubbo-monitor/dubbo-monitor-api/src/test/java/org/apache/dubbo/monitor/support/MonitorFilterTest.java

@@ -22,12 +22,14 @@ import org.apache.dubbo.common.utils.NetUtils;
 import org.apache.dubbo.monitor.Monitor;
 import org.apache.dubbo.monitor.MonitorFactory;
 import org.apache.dubbo.monitor.MonitorService;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
+
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
@@ -73,7 +75,7 @@ public class MonitorFilterTest {
 
         public Result invoke(Invocation invocation) throws RpcException {
             lastInvocation = invocation;
-            return null;
+            return AsyncRpcResult.newDefaultAsyncResult(invocation);
         }
 
         @Override
@@ -115,7 +117,11 @@ public class MonitorFilterTest {
         monitorFilter.setMonitorFactory(monitorFactory);
         Invocation invocation = new RpcInvocation("aaa", new Class<?>[0], new Object[0]);
         RpcContext.getContext().setRemoteAddress(NetUtils.getLocalHost(), 20880).setLocalAddress(NetUtils.getLocalHost(), 2345);
-        monitorFilter.invoke(serviceInvoker, invocation);
+        Result result = monitorFilter.invoke(serviceInvoker, invocation);
+        result.thenApplyWithContext((r) -> {
+            monitorFilter.listener().onResponse(r, serviceInvoker, invocation);
+            return r;
+        });
         while (lastStatistics == null) {
             Thread.sleep(10);
         }
@@ -151,7 +157,11 @@ public class MonitorFilterTest {
         monitorFilter.setMonitorFactory(monitorFactory);
         Invocation invocation = new RpcInvocation("$invoke", new Class<?>[]{String.class, String[].class, Object[].class}, new Object[]{"xxx", new String[]{}, new Object[]{}});
         RpcContext.getContext().setRemoteAddress(NetUtils.getLocalHost(), 20880).setLocalAddress(NetUtils.getLocalHost(), 2345);
-        monitorFilter.invoke(serviceInvoker, invocation);
+        Result result = monitorFilter.invoke(serviceInvoker, invocation);
+        result.thenApplyWithContext((r) -> {
+            monitorFilter.listener().onResponse(r, serviceInvoker, invocation);
+            return r;
+        });
         while (lastStatistics == null) {
             Thread.sleep(10);
         }

dubbo-registry/dubbo-registry-default/src/test/java/org/apache/dubbo/registry/dubbo/MockChannel.java

@@ -21,9 +21,9 @@ import org.apache.dubbo.remoting.ChannelHandler;
 import org.apache.dubbo.remoting.RemotingException;
 import org.apache.dubbo.remoting.exchange.ExchangeChannel;
 import org.apache.dubbo.remoting.exchange.ExchangeHandler;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
 
 import java.net.InetSocketAddress;
+import java.util.concurrent.CompletableFuture;
 
 public class MockChannel implements ExchangeChannel {
 
@@ -76,7 +76,7 @@ public class MockChannel implements ExchangeChannel {
         return null;
     }
 
-    public ResponseFuture send(Object request, int timeout) throws RemotingException {
+    public CompletableFuture<Object> send(Object request, int timeout) throws RemotingException {
         return null;
     }
 
@@ -85,11 +85,11 @@ public class MockChannel implements ExchangeChannel {
         return null;
     }
 
-    public ResponseFuture request(Object request) throws RemotingException {
+    public CompletableFuture<Object> request(Object request) throws RemotingException {
         return null;
     }
 
-    public ResponseFuture request(Object request, int timeout) throws RemotingException {
+    public CompletableFuture<Object> request(Object request, int timeout) throws RemotingException {
         return null;
     }
 

dubbo-registry/dubbo-registry-default/src/test/java/org/apache/dubbo/registry/dubbo/MockedClient.java

@@ -23,12 +23,13 @@ import org.apache.dubbo.remoting.Codec;
 import org.apache.dubbo.remoting.RemotingException;
 import org.apache.dubbo.remoting.exchange.ExchangeClient;
 import org.apache.dubbo.remoting.exchange.ExchangeHandler;
-import org.apache.dubbo.remoting.exchange.ResponseCallback;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
 import org.apache.dubbo.remoting.exchange.support.Replier;
 
 import java.net.InetSocketAddress;
 import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeoutException;
 
 /**
  * MockedClient
@@ -79,27 +80,24 @@ public class MockedClient implements ExchangeClient {
         this.sent = msg;
     }
 
-    public ResponseFuture request(Object msg) throws RemotingException {
+    public CompletableFuture<Object> request(Object msg) throws RemotingException {
         return request(msg, 0);
     }
 
-    public ResponseFuture request(Object msg, int timeout) throws RemotingException {
+    public CompletableFuture<Object> request(Object msg, int timeout) throws RemotingException {
         this.invoked = msg;
-        return new ResponseFuture() {
-            public Object get() throws RemotingException {
+        return new CompletableFuture<Object>() {
+            public Object get()  throws InterruptedException, ExecutionException {
                 return received;
             }
 
-            public Object get(int timeoutInMillis) throws RemotingException {
+            public Object get(int timeoutInMillis) throws InterruptedException, ExecutionException, TimeoutException {
                 return received;
             }
 
             public boolean isDone() {
                 return true;
             }
-
-            public void setCallback(ResponseCallback callback) {
-            }
         };
     }
 

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/RemotingException.java

@@ -22,8 +22,7 @@ import java.net.InetSocketAddress;
  * RemotingException. (API, Prototype, ThreadSafe)
  *
  * @export
- * @see org.apache.dubbo.remoting.exchange.ResponseFuture#get()
- * @see org.apache.dubbo.remoting.exchange.ResponseFuture#get(int)
+ * @see org.apache.dubbo.remoting.exchange.support.DefaultFuture#get()
  * @see org.apache.dubbo.remoting.Channel#send(Object, boolean)
  * @see org.apache.dubbo.remoting.exchange.ExchangeChannel#request(Object)
  * @see org.apache.dubbo.remoting.exchange.ExchangeChannel#request(Object, int)

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/TimeoutException.java

@@ -22,8 +22,7 @@ import java.net.InetSocketAddress;
  * TimeoutException. (API, Prototype, ThreadSafe)
  *
  * @export
- * @see org.apache.dubbo.remoting.exchange.ResponseFuture#get()
- * @see org.apache.dubbo.remoting.exchange.ResponseFuture#get(int)
+ * @see org.apache.dubbo.remoting.exchange.support.DefaultFuture#get()
  */
 public class TimeoutException extends RemotingException {
 

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/ExchangeChannel.java

@@ -19,6 +19,8 @@ package org.apache.dubbo.remoting.exchange;
 import org.apache.dubbo.remoting.Channel;
 import org.apache.dubbo.remoting.RemotingException;
 
+import java.util.concurrent.CompletableFuture;
+
 /**
  * ExchangeChannel. (API/SPI, Prototype, ThreadSafe)
  */
@@ -31,7 +33,7 @@ public interface ExchangeChannel extends Channel {
      * @return response future
      * @throws RemotingException
      */
-    ResponseFuture request(Object request) throws RemotingException;
+    CompletableFuture<Object> request(Object request) throws RemotingException;
 
     /**
      * send request.
@@ -41,7 +43,7 @@ public interface ExchangeChannel extends Channel {
      * @return response future
      * @throws RemotingException
      */
-    ResponseFuture request(Object request, int timeout) throws RemotingException;
+    CompletableFuture<Object> request(Object request, int timeout) throws RemotingException;
 
     /**
      * get message handler.

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/Response.java

@@ -16,6 +16,16 @@
  */
 package org.apache.dubbo.remoting.exchange;
 
+import org.apache.dubbo.remoting.Channel;
+import org.apache.dubbo.remoting.Codec;
+import org.apache.dubbo.remoting.Decodeable;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.HashMap;
+import java.util.Map;
+
 /**
  * Response
  */
@@ -173,4 +183,55 @@ public class Response {
         return "Response [id=" + mId + ", version=" + mVersion + ", status=" + mStatus + ", event=" + mEvent
                 + ", error=" + mErrorMsg + ", result=" + (mResult == this ? "this" : mResult) + "]";
     }
+
+    public static class AppResult {
+
+        protected Map<String, String> attachments = new HashMap<String, String>();
+
+        protected Object result;
+
+        protected Throwable exception;
+
+        public Map<String, String> getAttachments() {
+            return attachments;
+        }
+
+        public void setAttachments(Map<String, String> attachments) {
+            this.attachments = attachments;
+        }
+
+        public Object getResult() {
+            return result;
+        }
+
+        public void setResult(Object result) {
+            this.result = result;
+        }
+
+        public Throwable getException() {
+            return exception;
+        }
+
+        public void setException(Throwable exception) {
+            this.exception = exception;
+        }
+    }
+
+    public static class DecodeableAppResult implements Codec, Decodeable {
+
+        @Override
+        public void decode() throws Exception {
+
+        }
+
+        @Override
+        public void encode(Channel channel, OutputStream output, Object message) throws IOException {
+
+        }
+
+        @Override
+        public Object decode(Channel channel, InputStream input) throws IOException {
+            return null;
+        }
+    }
 }

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/ResponseFuture.java

@@ -1,58 +0,0 @@
-/*
- * 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.remoting.exchange;
-
-import org.apache.dubbo.remoting.RemotingException;
-
-/**
- * Future. (API/SPI, Prototype, ThreadSafe)
- *
- * @see org.apache.dubbo.remoting.exchange.ExchangeChannel#request(Object)
- * @see org.apache.dubbo.remoting.exchange.ExchangeChannel#request(Object, int)
- */
-public interface ResponseFuture {
-
-    /**
-     * get result.
-     *
-     * @return result.
-     */
-    Object get() throws RemotingException;
-
-    /**
-     * get result with the specified timeout.
-     *
-     * @param timeoutInMillis timeout.
-     * @return result.
-     */
-    Object get(int timeoutInMillis) throws RemotingException;
-
-    /**
-     * set callback.
-     *
-     * @param callback
-     */
-    void setCallback(ResponseCallback callback);
-
-    /**
-     * check is done.
-     *
-     * @return done or not.
-     */
-    boolean isDone();
-
-}

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/support/DefaultFuture.java

@@ -29,22 +29,18 @@ import org.apache.dubbo.remoting.RemotingException;
 import org.apache.dubbo.remoting.TimeoutException;
 import org.apache.dubbo.remoting.exchange.Request;
 import org.apache.dubbo.remoting.exchange.Response;
-import org.apache.dubbo.remoting.exchange.ResponseCallback;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
 
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.Map;
+import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.TimeUnit;
-import java.util.concurrent.locks.Condition;
-import java.util.concurrent.locks.Lock;
-import java.util.concurrent.locks.ReentrantLock;
 
 /**
  * DefaultFuture.
  */
-public class DefaultFuture implements ResponseFuture {
+public class DefaultFuture extends CompletableFuture<Object> {
 
     private static final Logger logger = LoggerFactory.getLogger(DefaultFuture.class);
 
@@ -62,12 +58,8 @@ public class DefaultFuture implements ResponseFuture {
     private final Channel channel;
     private final Request request;
     private final int timeout;
-    private final Lock lock = new ReentrantLock();
-    private final Condition done = lock.newCondition();
     private final long start = System.currentTimeMillis();
     private volatile long sent;
-    private volatile Response response;
-    private volatile ResponseCallback callback;
 
     private DefaultFuture(Channel channel, Request request, int timeout) {
         this.channel = channel;
@@ -79,14 +71,6 @@ public class DefaultFuture implements ResponseFuture {
         CHANNELS.put(id, channel);
     }
 
-    /**
-     * check time out of the future
-     */
-    private static void timeoutCheck(DefaultFuture future) {
-        TimeoutCheckTask task = new TimeoutCheckTask(future);
-        TIME_OUT_TIMER.newTimeout(task, future.getTimeout(), TimeUnit.MILLISECONDS);
-    }
-
     /**
      * init a DefaultFuture
      * 1.init a DefaultFuture
@@ -160,70 +144,77 @@ public class DefaultFuture implements ResponseFuture {
     }
 
     @Override
-    public Object get() throws RemotingException {
-        return get(timeout);
-    }
-
-    @Override
-    public Object get(int timeout) throws RemotingException {
-        if (timeout <= 0) {
-            timeout = Constants.DEFAULT_TIMEOUT;
-        }
-        if (!isDone()) {
-            long start = System.currentTimeMillis();
-            lock.lock();
-            try {
-                while (!isDone()) {
-                    done.await(timeout, TimeUnit.MILLISECONDS);
-                    if (isDone() || System.currentTimeMillis() - start > timeout) {
-                        break;
-                    }
-                }
-            } catch (InterruptedException e) {
-                throw new RuntimeException(e);
-            } finally {
-                lock.unlock();
-            }
-            if (!isDone()) {
-                throw new TimeoutException(sent > 0, channel, getTimeoutMessage(false));
-            }
-        }
-        return returnFromResponse();
+    public boolean cancel(boolean mayInterruptIfRunning) {
+        Response errorResult = new Response(id);
+        errorResult.setStatus(Response.CLIENT_ERROR);
+        errorResult.setErrorMessage("request future has been canceled.");
+        this.doReceived(errorResult);
+        FUTURES.remove(id);
+        CHANNELS.remove(id);
+        return true;
     }
 
     public void cancel() {
-        Response errorResult = new Response(id);
-        errorResult.setErrorMessage("request future has been canceled.");
-        response = errorResult;
-        FUTURES.remove(id);
-        CHANNELS.remove(id);
+        this.cancel(true);
     }
 
-    @Override
-    public boolean isDone() {
-        return response != null;
-    }
 
-    @Override
-    public void setCallback(ResponseCallback callback) {
-        if (isDone()) {
-            invokeCallback(callback);
-        } else {
-            boolean isdone = false;
-            lock.lock();
-            try {
-                if (!isDone()) {
-                    this.callback = callback;
-                } else {
-                    isdone = true;
-                }
-            } finally {
-                lock.unlock();
-            }
-            if (isdone) {
-                invokeCallback(callback);
-            }
+    private void doReceived(Response res) {
+        if (res == null) {
+            throw new IllegalStateException("response cannot be null");
         }
+        if (res.getStatus() == Response.OK) {
+            this.complete(res.getResult());
+        } else if (res.getStatus() == Response.CLIENT_TIMEOUT || res.getStatus() == Response.SERVER_TIMEOUT) {
+            this.completeExceptionally(new TimeoutException(res.getStatus() == Response.SERVER_TIMEOUT, channel, res.getErrorMessage()));
+        } else {
+            this.completeExceptionally(new RemotingException(channel, res.getErrorMessage()));
+        }
+    }
+
+    private long getId() {
+        return id;
+    }
+
+    private Channel getChannel() {
+        return channel;
+    }
+
+    private boolean isSent() {
+        return sent > 0;
+    }
+
+    public Request getRequest() {
+        return request;
+    }
+
+    private int getTimeout() {
+        return timeout;
+    }
+
+    private void doSent() {
+        sent = System.currentTimeMillis();
+    }
+
+    /**
+     * check time out of the future
+     */
+    private static void timeoutCheck(DefaultFuture future) {
+        TimeoutCheckTask task = new TimeoutCheckTask(future);
+        TIME_OUT_TIMER.newTimeout(task, future.getTimeout(), TimeUnit.MILLISECONDS);
+    }
+
+    private String getTimeoutMessage(boolean scan) {
+        long nowTimestamp = System.currentTimeMillis();
+        return (sent > 0 ? "Waiting server-side response timeout" : "Sending request timeout in client-side")
+                + (scan ? " by scan timer" : "") + ". start time: "
+                + (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS").format(new Date(start))) + ", end time: "
+                + (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS").format(new Date())) + ","
+                + (sent > 0 ? " client elapsed: " + (sent - start)
+                + " ms, server elapsed: " + (nowTimestamp - sent)
+                : " elapsed: " + (nowTimestamp - start)) + " ms, timeout: "
+                + timeout + " ms, request: " + request + ", channel: " + channel.getLocalAddress()
+                + " -> " + channel.getRemoteAddress();
     }
 
     private static class TimeoutCheckTask implements TimerTask {
@@ -249,105 +240,4 @@ public class DefaultFuture implements ResponseFuture {
 
         }
     }
-
-    private void invokeCallback(ResponseCallback c) {
-        ResponseCallback callbackCopy = c;
-        if (callbackCopy == null) {
-            throw new NullPointerException("callback cannot be null.");
-        }
-        Response res = response;
-        if (res == null) {
-            throw new IllegalStateException("response cannot be null. url:" + channel.getUrl());
-        }
-
-        if (res.getStatus() == Response.OK) {
-            try {
-                callbackCopy.done(res.getResult());
-            } catch (Exception e) {
-                logger.error("callback invoke error .result:" + res.getResult() + ",url:" + channel.getUrl(), e);
-            }
-        } else if (res.getStatus() == Response.CLIENT_TIMEOUT || res.getStatus() == Response.SERVER_TIMEOUT) {
-            try {
-                TimeoutException te = new TimeoutException(res.getStatus() == Response.SERVER_TIMEOUT, channel, res.getErrorMessage());
-                callbackCopy.caught(te);
-            } catch (Exception e) {
-                logger.error("callback invoke error ,url:" + channel.getUrl(), e);
-            }
-        } else {
-            try {
-                RuntimeException re = new RuntimeException(res.getErrorMessage());
-                callbackCopy.caught(re);
-            } catch (Exception e) {
-                logger.error("callback invoke error ,url:" + channel.getUrl(), e);
-            }
-        }
-    }
-
-    private Object returnFromResponse() throws RemotingException {
-        Response res = response;
-        if (res == null) {
-            throw new IllegalStateException("response cannot be null");
-        }
-        if (res.getStatus() == Response.OK) {
-            return res.getResult();
-        }
-        if (res.getStatus() == Response.CLIENT_TIMEOUT || res.getStatus() == Response.SERVER_TIMEOUT) {
-            throw new TimeoutException(res.getStatus() == Response.SERVER_TIMEOUT, channel, res.getErrorMessage());
-        }
-        throw new RemotingException(channel, res.getErrorMessage());
-    }
-
-    private long getId() {
-        return id;
-    }
-
-    private Channel getChannel() {
-        return channel;
-    }
-
-    private boolean isSent() {
-        return sent > 0;
-    }
-
-    public Request getRequest() {
-        return request;
-    }
-
-    private int getTimeout() {
-        return timeout;
-    }
-
-    private long getStartTimestamp() {
-        return start;
-    }
-
-    private void doSent() {
-        sent = System.currentTimeMillis();
-    }
-
-    private void doReceived(Response res) {
-        lock.lock();
-        try {
-            response = res;
-            done.signalAll();
-        } finally {
-            lock.unlock();
-        }
-        if (callback != null) {
-            invokeCallback(callback);
-        }
-    }
-
-    private String getTimeoutMessage(boolean scan) {
-        long nowTimestamp = System.currentTimeMillis();
-        return (sent > 0 ? "Waiting server-side response timeout" : "Sending request timeout in client-side")
-                + (scan ? " by scan timer" : "") + ". start time: "
-                + (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS").format(new Date(start))) + ", end time: "
-                + (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS").format(new Date())) + ","
-                + (sent > 0 ? " client elapsed: " + (sent - start)
-                + " ms, server elapsed: " + (nowTimestamp - sent)
-                : " elapsed: " + (nowTimestamp - start)) + " ms, timeout: "
-                + timeout + " ms, request: " + request + ", channel: " + channel.getLocalAddress()
-                + " -> " + channel.getRemoteAddress();
-    }
 }

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/support/SimpleFuture.java

@@ -1,54 +0,0 @@
-/*
- * 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.remoting.exchange.support;
-
-import org.apache.dubbo.remoting.RemotingException;
-import org.apache.dubbo.remoting.exchange.ResponseCallback;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
-
-/**
- * SimpleFuture
- */
-public class SimpleFuture implements ResponseFuture {
-
-    private final Object value;
-
-    public SimpleFuture(Object value) {
-        this.value = value;
-    }
-
-    @Override
-    public Object get() throws RemotingException {
-        return value;
-    }
-
-    @Override
-    public Object get(int timeoutInMillis) throws RemotingException {
-        return value;
-    }
-
-    @Override
-    public void setCallback(ResponseCallback callback) {
-        callback.done(value);
-    }
-
-    @Override
-    public boolean isDone() {
-        return true;
-    }
-
-}

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/support/header/HeaderExchangeChannel.java

@@ -28,10 +28,10 @@ import org.apache.dubbo.remoting.exchange.ExchangeChannel;
 import org.apache.dubbo.remoting.exchange.ExchangeHandler;
 import org.apache.dubbo.remoting.exchange.Request;
 import org.apache.dubbo.remoting.exchange.Response;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
 import org.apache.dubbo.remoting.exchange.support.DefaultFuture;
 
 import java.net.InetSocketAddress;
+import java.util.concurrent.CompletableFuture;
 
 /**
  * ExchangeReceiver
@@ -97,12 +97,12 @@ final class HeaderExchangeChannel implements ExchangeChannel {
     }
 
     @Override
-    public ResponseFuture request(Object request) throws RemotingException {
+    public CompletableFuture<Object> request(Object request) throws RemotingException {
         return request(request, channel.getUrl().getPositiveParameter(Constants.TIMEOUT_KEY, Constants.DEFAULT_TIMEOUT));
     }
 
     @Override
-    public ResponseFuture request(Object request, int timeout) throws RemotingException {
+    public CompletableFuture<Object> request(Object request, int timeout) throws RemotingException {
         if (closed) {
             throw new RemotingException(this.getLocalAddress(), null, "Failed to send request " + request + ", cause: The channel " + this + " is closed!");
         }

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/support/header/HeaderExchangeClient.java

@@ -27,10 +27,10 @@ import org.apache.dubbo.remoting.RemotingException;
 import org.apache.dubbo.remoting.exchange.ExchangeChannel;
 import org.apache.dubbo.remoting.exchange.ExchangeClient;
 import org.apache.dubbo.remoting.exchange.ExchangeHandler;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
 
 import java.net.InetSocketAddress;
 import java.util.Collections;
+import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.TimeUnit;
 
 import static org.apache.dubbo.common.utils.UrlUtils.getHeartbeat;
@@ -62,7 +62,7 @@ public class HeaderExchangeClient implements ExchangeClient {
     }
 
     @Override
-    public ResponseFuture request(Object request) throws RemotingException {
+    public CompletableFuture<Object> request(Object request) throws RemotingException {
         return channel.request(request);
     }
 
@@ -77,7 +77,7 @@ public class HeaderExchangeClient implements ExchangeClient {
     }
 
     @Override
-    public ResponseFuture request(Object request, int timeout) throws RemotingException {
+    public CompletableFuture<Object> request(Object request, int timeout) throws RemotingException {
         return channel.request(request, timeout);
     }
 

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/support/header/HeaderExchangeHandler.java

@@ -34,7 +34,7 @@ import org.apache.dubbo.remoting.exchange.support.DefaultFuture;
 import org.apache.dubbo.remoting.transport.ChannelHandlerDelegate;
 
 import java.net.InetSocketAddress;
-import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
 
 
 /**
@@ -99,19 +99,12 @@ public class HeaderExchangeHandler implements ChannelHandlerDelegate {
         // find handler by message class.
         Object msg = req.getData();
         try {
-            // handle data.
-            CompletableFuture<Object> future = handler.reply(channel, msg);
-            if (future.isDone()) {
-                res.setStatus(Response.OK);
-                res.setResult(future.get());
-                channel.send(res);
-                return;
-            }
-            future.whenComplete((result, t) -> {
+            CompletionStage<Object> future = handler.reply(channel, msg);
+            future.whenComplete((appResult, t) -> {
                 try {
                     if (t == null) {
                         res.setStatus(Response.OK);
-                        res.setResult(result);
+                        res.setResult(appResult);
                     } else {
                         res.setStatus(Response.SERVICE_ERROR);
                         res.setErrorMessage(StringUtils.toString(t));

dubbo-remoting/dubbo-remoting-api/src/test/java/org/apache/dubbo/remoting/Main.java

@@ -19,12 +19,12 @@ package org.apache.dubbo.remoting;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.remoting.exchange.ExchangeChannel;
 import org.apache.dubbo.remoting.exchange.Exchangers;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
 import org.apache.dubbo.remoting.exchange.support.Replier;
 import org.apache.dubbo.remoting.exchange.support.ReplierDispatcher;
 
 import java.io.Serializable;
 import java.util.Random;
+import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.Executor;
 import java.util.concurrent.Executors;
 
@@ -94,7 +94,7 @@ public class Main {
 
         System.out.println("=====test invoke=====");
         for (int i = 0; i < 100; i++) {
-            ResponseFuture future = client.request(new Main.Data());
+            CompletableFuture<Object> future = client.request(new Main.Data());
             System.out.println("invoke and get");
             System.out.println("invoke result:" + future.get());
         }

dubbo-remoting/dubbo-remoting-api/src/test/java/org/apache/dubbo/remoting/PerformanceServerTest.java

@@ -25,7 +25,6 @@ import org.apache.dubbo.remoting.exchange.Exchangers;
 import org.apache.dubbo.remoting.exchange.support.ExchangeHandlerAdapter;
 import org.apache.dubbo.remoting.transport.dispatcher.execution.ExecutionDispatcher;
 
-import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 import java.util.ArrayList;

dubbo-remoting/dubbo-remoting-api/src/test/java/org/apache/dubbo/remoting/exchange/support/DefaultFutureTest.java

@@ -74,7 +74,7 @@ public class DefaultFutureTest {
         try {
             f.get();
         } catch (Exception e) {
-            Assertions.assertTrue(e instanceof TimeoutException, "catch exception is not timeout exception!");
+            Assertions.assertTrue(e.getCause() instanceof TimeoutException, "catch exception is not timeout exception!");
             System.out.println(e.getMessage());
         }
     }
@@ -108,7 +108,7 @@ public class DefaultFutureTest {
         try {
             f.get();
         } catch (Exception e) {
-            Assertions.assertTrue(e instanceof TimeoutException, "catch exception is not timeout exception!");
+            Assertions.assertTrue(e.getCause() instanceof TimeoutException, "catch exception is not timeout exception!");
             System.out.println(e.getMessage());
         }
     }

dubbo-remoting/dubbo-remoting-api/src/test/java/org/apache/dubbo/remoting/handler/HeaderExchangeHandlerTest.java

@@ -178,7 +178,7 @@ public class HeaderExchangeHandlerTest {
         HeaderExchangeHandler hexhandler = new HeaderExchangeHandler(new MockedExchangeHandler() {
 
             @Override
-            public CompletableFuture reply(ExchangeChannel channel, Object request) throws RemotingException {
+            public CompletableFuture<Object> reply(ExchangeChannel channel, Object request) throws RemotingException {
                 Assertions.fail();
                 throw new RemotingException(channel, "");
             }

dubbo-remoting/dubbo-remoting-mina/src/test/java/org/apache/remoting/transport/mina/ClientToServerTest.java

@@ -19,7 +19,6 @@ package org.apache.remoting.transport.mina;
 import org.apache.dubbo.remoting.RemotingException;
 import org.apache.dubbo.remoting.exchange.ExchangeChannel;
 import org.apache.dubbo.remoting.exchange.ExchangeServer;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
 import org.apache.dubbo.remoting.exchange.support.Replier;
 
 import org.junit.jupiter.api.AfterEach;
@@ -27,6 +26,8 @@ import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+import java.util.concurrent.CompletableFuture;
+
 /**
  * ClientToServer
  */
@@ -64,7 +65,7 @@ public abstract class ClientToServerTest {
 
     @Test
     public void testFuture() throws Exception {
-        ResponseFuture future = client.request(new World("world"));
+        CompletableFuture<Object> future = client.request(new World("world"));
         Hello result = (Hello) future.get();
         Assertions.assertEquals("hello,world", result.getName());
     }

dubbo-remoting/dubbo-remoting-netty/src/test/java/org/apache/dubbo/remoting/exchange/support/header/HeartbeatHandlerTest.java

@@ -29,6 +29,7 @@ import org.apache.dubbo.remoting.exchange.ExchangeHandler;
 import org.apache.dubbo.remoting.exchange.ExchangeServer;
 import org.apache.dubbo.remoting.exchange.Exchangers;
 import org.apache.dubbo.remoting.transport.dispatcher.FakeChannelHandlers;
+
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;

dubbo-remoting/dubbo-remoting-netty/src/test/java/org/apache/dubbo/remoting/transport/netty/ClientToServerTest.java

@@ -19,14 +19,14 @@ package org.apache.dubbo.remoting.transport.netty;
 import org.apache.dubbo.remoting.RemotingException;
 import org.apache.dubbo.remoting.exchange.ExchangeChannel;
 import org.apache.dubbo.remoting.exchange.ExchangeServer;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
 import org.apache.dubbo.remoting.exchange.support.Replier;
 
-import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+import java.util.concurrent.CompletableFuture;
+
 /**
  * ClientToServer
  */
@@ -64,7 +64,7 @@ public abstract class ClientToServerTest  {
 
     @Test
     public void testFuture() throws Exception {
-        ResponseFuture future = client.request(new World("world"));
+        CompletableFuture<Object> future = client.request(new World("world"));
         Hello result = (Hello) future.get();
         Assertions.assertEquals("hello,world", result.getName());
     }

dubbo-remoting/dubbo-remoting-netty4/src/test/java/org/apache/dubbo/remoting/transport/netty4/ClientToServerTest.java

@@ -19,7 +19,6 @@ package org.apache.dubbo.remoting.transport.netty4;
 import org.apache.dubbo.remoting.RemotingException;
 import org.apache.dubbo.remoting.exchange.ExchangeChannel;
 import org.apache.dubbo.remoting.exchange.ExchangeServer;
-import org.apache.dubbo.remoting.exchange.ResponseFuture;
 import org.apache.dubbo.remoting.exchange.support.Replier;
 
 import org.junit.jupiter.api.AfterEach;
@@ -27,6 +26,8 @@ import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+import java.util.concurrent.CompletableFuture;
+
 /**
  * ClientToServer
  */
@@ -64,7 +65,7 @@ public abstract class ClientToServerTest {
 
     @Test
     public void testFuture() throws Exception {
-        ResponseFuture future = client.request(new World("world"));
+        CompletableFuture<Object> future = client.request(new World("world"));
         Hello result = (Hello) future.get();
         Assertions.assertEquals("hello,world", result.getName());
     }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/AbstractResult.java

@@ -1,74 +0,0 @@
-/*
- * 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;
-
-import org.apache.dubbo.common.utils.StringUtils;
-
-import java.util.HashMap;
-import java.util.Map;
-
-/**
- *
- */
-public abstract class AbstractResult implements Result {
-    protected Map<String, String> attachments = new HashMap<String, String>();
-
-    protected Object result;
-
-    protected Throwable exception;
-
-    @Override
-    public Map<String, String> getAttachments() {
-        return attachments;
-    }
-
-    @Override
-    public void setAttachments(Map<String, String> map) {
-        this.attachments = map == null ? new HashMap<String, String>() : map;
-    }
-
-    @Override
-    public void addAttachments(Map<String, String> map) {
-        if (map == null) {
-            return;
-        }
-        if (this.attachments == null) {
-            this.attachments = new HashMap<String, String>();
-        }
-        this.attachments.putAll(map);
-    }
-
-    @Override
-    public String getAttachment(String key) {
-        return attachments.get(key);
-    }
-
-    @Override
-    public String getAttachment(String key, String defaultValue) {
-        String result = attachments.get(key);
-        if (StringUtils.isEmpty(result)) {
-            result = defaultValue;
-        }
-        return result;
-    }
-
-    @Override
-    public void setAttachment(String key, String value) {
-        attachments.put(key, value);
-    }
-
-}

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/AppResponse.java

@@ -0,0 +1,160 @@
+/*
+ * 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;
+
+import java.io.Serializable;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.function.Function;
+
+/**
+ * {@link AsyncRpcResult} is introduced in 3.0.0 to replace RpcResult, and RpcResult is replaced with {@link AppResponse}:
+ * <ul>
+ *     <li>AsyncRpcResult is the object that is actually passed in the call chain</li>
+ *     <li>AppResponse only simply represents the business result</li>
+ * </ul>
+ *
+ *  The relationship between them can be reflected in the definition of AsyncRpcResult:
+ *  <pre>
+ *  {@code
+ *   Public class AsyncRpcResult implements Result {
+ *      private CompletableFuture <AppResponse> resultFuture;
+ *       ......
+ *   }
+ *  }
+ * </pre>
+ *
+ * In theory, AppResponse does not need to implement the {@link Result} interface, this is done mainly for compatibility purpose.
+ *
+ * @serial Do not change the class name and properties.
+ */
+public class AppResponse implements Result, Serializable {
+
+    private static final long serialVersionUID = -6925924956850004727L;
+
+    private Object result;
+
+    private Throwable exception;
+
+    private Map<String, String> attachments = new HashMap<String, String>();
+
+    public AppResponse() {
+    }
+
+    public AppResponse(Object result) {
+        this.result = result;
+    }
+
+    public AppResponse(Throwable exception) {
+        this.exception = exception;
+    }
+
+    @Override
+    public Object recreate() throws Throwable {
+        if (exception != null) {
+            throw exception;
+        }
+        return result;
+    }
+
+    @Override
+    public Object getValue() {
+        return result;
+    }
+
+    public void setValue(Object value) {
+        this.result = value;
+    }
+
+    @Override
+    public Throwable getException() {
+        return exception;
+    }
+
+    public void setException(Throwable e) {
+        this.exception = e;
+    }
+
+    @Override
+    public boolean hasException() {
+        return exception != null;
+    }
+
+    @Override
+    public Map<String, String> getAttachments() {
+        return attachments;
+    }
+
+    /**
+     * Append all items from the map into the attachment, if map is empty then nothing happens
+     *
+     * @param map contains all key-value pairs to append
+     */
+    public void setAttachments(Map<String, String> map) {
+        this.attachments = map == null ? new HashMap<String, String>() : map;
+    }
+
+    public void addAttachments(Map<String, String> map) {
+        if (map == null) {
+            return;
+        }
+        if (this.attachments == null) {
+            this.attachments = new HashMap<String, String>();
+        }
+        this.attachments.putAll(map);
+    }
+
+    @Override
+    public String getAttachment(String key) {
+        return attachments.get(key);
+    }
+
+    @Override
+    public String getAttachment(String key, String defaultValue) {
+        String result = attachments.get(key);
+        if (result == null || result.length() == 0) {
+            result = defaultValue;
+        }
+        return result;
+    }
+
+    public void setAttachment(String key, String value) {
+        attachments.put(key, value);
+    }
+
+    @Override
+    public Result thenApplyWithContext(Function<AppResponse, AppResponse> fn) {
+        throw new UnsupportedOperationException("AppResponse represents an concrete business response, there will be no status changes, you should get internal values directly.");
+    }
+
+    @Override
+    public <U> CompletableFuture<U> thenApply(Function<Result, ? extends U> fn) {
+        throw new UnsupportedOperationException("AppResponse represents an concrete business response, there will be no status changes, you should get internal values directly.");
+    }
+
+    @Override
+    public Result get() throws InterruptedException, ExecutionException {
+        throw new UnsupportedOperationException("AppResponse represents an concrete business response, there will be no status changes, you should get internal values directly.");
+    }
+
+    @Override
+    public String toString() {
+        return "AppResponse [value=" + result + ", exception=" + exception + "]";
+    }
+}

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/AsyncRpcResult.java

@@ -22,96 +22,27 @@ import org.apache.dubbo.common.logger.LoggerFactory;
 import java.util.Map;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CompletionException;
+import java.util.concurrent.ExecutionException;
 import java.util.function.Function;
 
-/**
- * <b>NOTICE!!</b>
- *
- * <p>
- * You should never rely on this class directly when using or extending Dubbo, the implementation of {@link AsyncRpcResult}
- * is only a workaround for compatibility purpose. It may be changed or even get removed from the next major version.
- * Please only use {@link Result} or {@link RpcResult}.
- *
- * Extending the {@link Filter} is one typical use case:
- * <pre>
- * {@code
- * public class YourFilter implements Filter {
- *     @Override
- *     public Result onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
- *         System.out.println("Filter get the return value: " + result.getValue());
- *         // Don't do this
- *         // AsyncRpcResult asyncRpcResult = ((AsyncRpcResult)result;
- *         // System.out.println("Filter get the return value: " + asyncRpcResult.getValue());
- *         return result;
- *     }
- *
- *     @Override
- *     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
- *         return invoker.invoke(invocation);
- *     }
- * }
- * }
- * </pre>
- * </p>
- * TODO RpcResult can be an instance of {@link java.util.concurrent.CompletionStage} instead of composing CompletionStage inside.
- */
-public class AsyncRpcResult extends AbstractResult {
+public class AsyncRpcResult implements Result {
     private static final Logger logger = LoggerFactory.getLogger(AsyncRpcResult.class);
 
     /**
-     * RpcContext can be changed, because thread may have been used by other thread. It should be cloned before store.
-     * So we use Invocation instead, Invocation will create for every invoke, but invocation only support attachments of string type.
+     * RpcContext may already have been changed when callback happens, it happens when the same thread is used to execute another RPC call.
+     * So we should keep the reference of current RpcContext instance and restore it before callback being executed.
      */
     private RpcContext storedContext;
     private RpcContext storedServerContext;
 
-    protected CompletableFuture<Object> valueFuture;
+    private CompletableFuture<AppResponse> responseFuture;
+    private Invocation invocation;
 
-    protected CompletableFuture<Result> resultFuture;
-
-    public AsyncRpcResult(CompletableFuture<Object> future) {
-        this(future, true);
-    }
-
-    public AsyncRpcResult(CompletableFuture<Object> future, boolean registerCallback) {
-        this(future, new CompletableFuture<>(), registerCallback);
-    }
-
-    /**
-     * @param future
-     * @param rFuture
-     * @param registerCallback
-     */
-    public AsyncRpcResult(CompletableFuture<Object> future, final CompletableFuture<Result> rFuture, boolean registerCallback) {
-        if (rFuture == null) {
-            throw new IllegalArgumentException();
-        }
-        resultFuture = rFuture;
-        if (registerCallback) {
-            /**
-             * We do not know whether future already completed or not, it's a future exposed or even created by end user.
-             * 1. future complete before whenComplete. whenComplete fn (resultFuture.complete) will be executed in thread subscribing, in our case, it's Dubbo thread.
-             * 2. future complete after whenComplete. whenComplete fn (resultFuture.complete) will be executed in thread calling complete, normally its User thread.
-             */
-            future.whenComplete((v, t) -> {
-                RpcResult rpcResult;
-                if (t != null) {
-                    if (t instanceof CompletionException) {
-                        rpcResult = new RpcResult(t.getCause());
-                    } else {
-                        rpcResult = new RpcResult(t);
-                    }
-                } else {
-                    rpcResult = new RpcResult(v);
-                }
-                // instead of resultFuture we must use rFuture here, resultFuture may being changed before complete when building filter chain, but rFuture was guaranteed never changed by closure.
-                rFuture.complete(rpcResult);
-            });
-        }
-        this.valueFuture = future;
-        // employ copy of context avoid the other call may modify the context content
-        this.storedContext = RpcContext.getContext().copyOf();
-        this.storedServerContext = RpcContext.getServerContext().copyOf();
+    public AsyncRpcResult(CompletableFuture<AppResponse> future, Invocation invocation) {
+        this.responseFuture = future;
+        this.invocation = invocation;
+        this.storedContext = RpcContext.getContext();
+        this.storedServerContext = RpcContext.getServerContext();
     }
 
     @Override
@@ -119,52 +50,87 @@ public class AsyncRpcResult extends AbstractResult {
         return getRpcResult().getValue();
     }
 
+    @Override
+    public void setValue(Object value) {
+
+    }
+
     @Override
     public Throwable getException() {
         return getRpcResult().getException();
     }
 
+    @Override
+    public void setException(Throwable t) {
+
+    }
+
     @Override
     public boolean hasException() {
         return getRpcResult().hasException();
     }
 
-    @Override
-    public Object getResult() {
-        return getRpcResult().getResult();
+    public CompletableFuture<AppResponse> getResponseFuture() {
+        return responseFuture;
     }
 
-    public CompletableFuture getValueFuture() {
-        return valueFuture;
-    }
-
-    public CompletableFuture<Result> getResultFuture() {
-        return resultFuture;
-    }
-
-    public void setResultFuture(CompletableFuture<Result> resultFuture) {
-        this.resultFuture = resultFuture;
+    public void setResponseFuture(CompletableFuture<AppResponse> responseFuture) {
+        this.responseFuture = responseFuture;
     }
 
     public Result getRpcResult() {
         try {
-            if (resultFuture.isDone()) {
-                return resultFuture.get();
+            if (responseFuture.isDone()) {
+                return responseFuture.get();
             }
         } catch (Exception e) {
             // This should never happen;
             logger.error("Got exception when trying to fetch the underlying result from AsyncRpcResult.", e);
         }
-        return new RpcResult();
+        return new AppResponse();
     }
 
     @Override
     public Object recreate() throws Throwable {
-        return valueFuture;
+        RpcInvocation rpcInvocation = (RpcInvocation) invocation;
+        if (InvokeMode.FUTURE == rpcInvocation.getInvokeMode()) {
+            AppResponse rpcResult = new AppResponse();
+            CompletableFuture<Object> future = new CompletableFuture<>();
+            rpcResult.setValue(future);
+            responseFuture.whenComplete((result, t) -> {
+                if (t != null) {
+                    if (t instanceof CompletionException) {
+                        t = t.getCause();
+                    }
+                    future.completeExceptionally(t);
+                } else {
+                    if (result.hasException()) {
+                        future.completeExceptionally(result.getException());
+                    } else {
+                        future.complete(result.getValue());
+                    }
+                }
+            });
+            return rpcResult.recreate();
+        } else if (responseFuture.isDone()) {
+            return responseFuture.get().recreate();
+        }
+        return (new AppResponse()).recreate();
     }
 
-    public void thenApplyWithContext(Function<Result, Result> fn) {
-        this.resultFuture = resultFuture.thenApply(fn.compose(beforeContext).andThen(afterContext));
+    public Result get() throws InterruptedException, ExecutionException {
+        return responseFuture.get();
+    }
+
+    @Override
+    public Result thenApplyWithContext(Function<AppResponse, AppResponse> fn) {
+        this.responseFuture = responseFuture.thenApply(fn.compose(beforeContext).andThen(afterContext));
+        return this;
+    }
+
+    @Override
+    public <U> CompletableFuture<U> thenApply(Function<Result,? extends U> fn) {
+        return this.responseFuture.thenApply(fn);
     }
 
     @Override
@@ -203,18 +169,49 @@ public class AsyncRpcResult extends AbstractResult {
     private RpcContext tmpContext;
     private RpcContext tmpServerContext;
 
-    private Function<Result, Result> beforeContext = (result) -> {
+    private Function<AppResponse, AppResponse> beforeContext = (appResponse) -> {
         tmpContext = RpcContext.getContext();
         tmpServerContext = RpcContext.getServerContext();
         RpcContext.restoreContext(storedContext);
         RpcContext.restoreServerContext(storedServerContext);
-        return result;
+        return appResponse;
     };
 
-    private Function<Result, Result> afterContext = (result) -> {
+    private Function<AppResponse, AppResponse> afterContext = (appResponse) -> {
         RpcContext.restoreContext(tmpContext);
         RpcContext.restoreServerContext(tmpServerContext);
-        return result;
+        return appResponse;
     };
+
+    /**
+     * Some utility methods used to quickly generate default AsyncRpcResult instance.
+     */
+    public static AsyncRpcResult newDefaultAsyncResult(AppResponse result, Invocation invocation) {
+        return new AsyncRpcResult(CompletableFuture.completedFuture(result), invocation);
+    }
+
+    public static AsyncRpcResult newDefaultAsyncResult(Invocation invocation) {
+        return newDefaultAsyncResult(null, null, invocation);
+    }
+
+    public static AsyncRpcResult newDefaultAsyncResult(Object value, Invocation invocation) {
+        return newDefaultAsyncResult(value, null, invocation);
+    }
+
+    public static AsyncRpcResult newDefaultAsyncResult(Throwable t, Invocation invocation) {
+        return newDefaultAsyncResult(null, t, invocation);
+    }
+
+    public static AsyncRpcResult newDefaultAsyncResult(Object value, Throwable t, Invocation invocation) {
+        CompletableFuture<AppResponse> future = new CompletableFuture<>();
+        AppResponse result = new AppResponse();
+        if (t != null) {
+            result.setException(t);
+        } else {
+            result.setValue(value);
+        }
+        future.complete(result);
+        return new AsyncRpcResult(future, invocation);
+    }
 }
 

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/Filter.java

@@ -42,27 +42,16 @@ import org.apache.dubbo.common.extension.SPI;
  */
 @SPI
 public interface Filter {
-
     /**
-     * do invoke filter.
-     * <p>
-     * <code>
-     * // before filter
-     * Result result = invoker.invoke(invocation);
-     * // after filter
-     * return result;
-     * </code>
-     *
-     * @param invoker    service
-     * @param invocation invocation.
-     * @return invoke result.
-     * @throws RpcException
-     * @see org.apache.dubbo.rpc.Invoker#invoke(Invocation)
+     * Does not need to override/implement this method.
      */
     Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException;
 
-    default Result onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
-        return result;
+    interface Listener {
+
+        void onResponse(Result result, Invoker<?> invoker, Invocation invocation);
+
+        void onError(Throwable t, Invoker<?> invoker, Invocation invocation);
     }
 
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/FutureContext.java

@@ -0,0 +1,52 @@
+/*
+ * 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;
+
+import java.util.concurrent.CompletableFuture;
+
+/**
+ * Used for async call scenario. But if the method you are calling has a {@link CompletableFuture<?>} signature
+ * you do not need to use this class since you will get a Future response directly.
+ * <p>
+ * Remember to save the Future reference before making another call using the same thread, otherwise,
+ * the current Future will be override by the new one, which means you will lose the chance get the return value.
+ */
+public class FutureContext {
+
+    public static ThreadLocal<CompletableFuture<?>> futureTL = new ThreadLocal<>();
+
+    /**
+     * get future.
+     *
+     * @param <T>
+     * @return future
+     */
+    @SuppressWarnings("unchecked")
+    public static <T> CompletableFuture<T> getCompletableFuture() {
+        return (CompletableFuture<T>) futureTL.get();
+    }
+
+    /**
+     * set future.
+     *
+     * @param future
+     */
+    public static void setFuture(CompletableFuture<?> future) {
+        futureTL.set(future);
+    }
+
+}

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/Invocation.java

@@ -59,6 +59,10 @@ public interface Invocation {
      */
     Map<String, String> getAttachments();
 
+    void setAttachment(String key, String value);
+
+    void setAttachmentIfAbsent(String key, String value);
+
     /**
      * get attachment by key.
      *

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/InvokeMode.java

@@ -0,0 +1,23 @@
+/*
+ * 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;
+
+public enum InvokeMode {
+
+    SYNC, ASYNC, FUTURE;
+
+}

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/ListenableFilter.java

@@ -1,38 +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.remoting.exchange;
-
-/**
- * Callback
- */
-public interface ResponseCallback {
-
-    /**
-     * done.
-     *
-     * @param response
-     */
-    void done(Object response);
-
-    /**
-     * caught exception.
-     *
-     * @param exception
-     */
-    void caught(Throwable exception);
-
-}
+/*
+ * 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;
+
+/**
+ *
+ */
+public abstract class ListenableFilter implements Filter {
+
+    protected Listener listener = null;
+
+    public Listener listener() {
+        return listener;
+    }
+}

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/Result.java

@@ -18,6 +18,9 @@ package org.apache.dubbo.rpc;
 
 import java.io.Serializable;
 import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.function.Function;
 
 
 /**
@@ -25,7 +28,7 @@ import java.util.Map;
  *
  * @serial Don't change the class name and package name.
  * @see org.apache.dubbo.rpc.Invoker#invoke(Invocation)
- * @see org.apache.dubbo.rpc.RpcResult
+ * @see AppResponse
  */
 public interface Result extends Serializable {
 
@@ -36,6 +39,8 @@ public interface Result extends Serializable {
      */
     Object getValue();
 
+    void setValue(Object value);
+
     /**
      * Get exception.
      *
@@ -43,6 +48,8 @@ public interface Result extends Serializable {
      */
     Throwable getException();
 
+    void setException(Throwable t);
+
     /**
      * Has exception.
      *
@@ -66,14 +73,6 @@ public interface Result extends Serializable {
      */
     Object recreate() throws Throwable;
 
-    /**
-     * @see org.apache.dubbo.rpc.Result#getValue()
-     * @deprecated Replace to getValue()
-     */
-    @Deprecated
-    Object getResult();
-
-
     /**
      * get attachments.
      *
@@ -111,4 +110,10 @@ public interface Result extends Serializable {
 
     void setAttachment(String key, String value);
 
+    Result thenApplyWithContext(Function<AppResponse, AppResponse> fn);
+
+    <U> CompletableFuture<U> thenApply(Function<Result, ? extends U> fn);
+
+    Result get() throws InterruptedException, ExecutionException;
+
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/RpcContext.java

@@ -70,7 +70,6 @@ public class RpcContext {
 
     private final Map<String, String> attachments = new HashMap<String, String>();
     private final Map<String, Object> values = new HashMap<String, Object>();
-    private Future<?> future;
 
     private List<URL> urls;
 
@@ -136,31 +135,6 @@ public class RpcContext {
         LOCAL.set(oldContext);
     }
 
-
-    public RpcContext copyOf() {
-        RpcContext copy = new RpcContext();
-        copy.attachments.putAll(this.attachments);
-        copy.values.putAll(this.values);
-        copy.future = this.future;
-        copy.urls = this.urls;
-        copy.url = this.url;
-        copy.methodName = this.methodName;
-        copy.parameterTypes = this.parameterTypes;
-        copy.arguments = this.arguments;
-        copy.localAddress = this.localAddress;
-        copy.remoteAddress = this.remoteAddress;
-        copy.invokers = this.invokers;
-        copy.invoker = this.invoker;
-        copy.invocation = this.invocation;
-
-        copy.request = this.request;
-        copy.response = this.response;
-        copy.asyncContext = this.asyncContext;
-
-        return copy;
-    }
-
-
     /**
      * remove context.
      *
@@ -242,7 +216,7 @@ public class RpcContext {
      */
     @SuppressWarnings("unchecked")
     public <T> CompletableFuture<T> getCompletableFuture() {
-        return (CompletableFuture<T>) future;
+        return FutureContext.getCompletableFuture();
     }
 
     /**
@@ -253,7 +227,7 @@ public class RpcContext {
      */
     @SuppressWarnings("unchecked")
     public <T> Future<T> getFuture() {
-        return (Future<T>) future;
+        return FutureContext.getCompletableFuture();
     }
 
     /**
@@ -261,8 +235,8 @@ public class RpcContext {
      *
      * @param future
      */
-    public void setFuture(Future<?> future) {
-        this.future = future;
+    public void setFuture(CompletableFuture<?> future) {
+        FutureContext.setFuture(future);
     }
 
     public List<URL> getUrls() {

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/RpcInvocation.java

@@ -47,6 +47,10 @@ public class RpcInvocation implements Invocation, Serializable {
 
     private transient Invoker<?> invoker;
 
+    private transient Class<?> returnType;
+
+    private transient InvokeMode invokeMode;
+
     public RpcInvocation() {
     }
 
@@ -89,6 +93,7 @@ public class RpcInvocation implements Invocation, Serializable {
 
     public RpcInvocation(Method method, Object[] arguments, Map<String, String> attachment) {
         this(method.getName(), method.getParameterTypes(), arguments, attachment, null);
+        this.returnType = method.getReturnType();
     }
 
     public RpcInvocation(String methodName, Class<?>[] parameterTypes, Object[] arguments) {
@@ -220,6 +225,22 @@ public class RpcInvocation implements Invocation, Serializable {
         return value;
     }
 
+    public Class<?> getReturnType() {
+        return returnType;
+    }
+
+    public void setReturnType(Class<?> returnType) {
+        this.returnType = returnType;
+    }
+
+    public InvokeMode getInvokeMode() {
+        return invokeMode;
+    }
+
+    public void setInvokeMode(InvokeMode invokeMode) {
+        this.invokeMode = invokeMode;
+    }
+
     @Override
     public String toString() {
         return "RpcInvocation [methodName=" + methodName + ", parameterTypes="

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/RpcResult.java

@@ -1,112 +0,0 @@
-/*
- * 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;
-
-import java.lang.reflect.Field;
-
-/**
- * RPC Result.
- *
- * @serial Don't change the class name and properties.
- */
-public class RpcResult extends AbstractResult {
-
-    private static final long serialVersionUID = -6925924956850004727L;
-
-    public RpcResult() {
-    }
-
-    public RpcResult(Object result) {
-        this.result = result;
-    }
-
-    public RpcResult(Throwable exception) {
-        this.exception = exception;
-    }
-
-    @Override
-    public Object recreate() throws Throwable {
-        if (exception != null) {
-            // fix issue#619
-            try {
-                // get Throwable class
-                Class clazz = exception.getClass();
-                while (!clazz.getName().equals(Throwable.class.getName())) {
-                    clazz = clazz.getSuperclass();
-                }
-                // get stackTrace value
-                Field stackTraceField = clazz.getDeclaredField("stackTrace");
-                stackTraceField.setAccessible(true);
-                Object stackTrace = stackTraceField.get(exception);
-                if (stackTrace == null) {
-                    exception.setStackTrace(new StackTraceElement[0]);
-                }
-            } catch (Exception e) {
-                // ignore
-            }
-            throw exception;
-        }
-        return result;
-    }
-
-    /**
-     * @see org.apache.dubbo.rpc.RpcResult#getValue()
-     * @deprecated Replace to getValue()
-     */
-    @Override
-    @Deprecated
-    public Object getResult() {
-        return getValue();
-    }
-
-    /**
-     * @see org.apache.dubbo.rpc.RpcResult#setValue(Object)
-     * @deprecated Replace to setValue()
-     */
-    @Deprecated
-    public void setResult(Object result) {
-        setValue(result);
-    }
-
-    @Override
-    public Object getValue() {
-        return result;
-    }
-
-    public void setValue(Object value) {
-        this.result = value;
-    }
-
-    @Override
-    public Throwable getException() {
-        return exception;
-    }
-
-    public void setException(Throwable e) {
-        this.exception = e;
-    }
-
-    @Override
-    public boolean hasException() {
-        return exception != null;
-    }
-
-    @Override
-    public String toString() {
-        return "RpcResult [result=" + result + ", exception=" + exception + "]";
-    }
-}

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/SimpleAsyncRpcResult.java

@@ -1,50 +0,0 @@
-/*
- * 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;
-
-import java.util.concurrent.CompletableFuture;
-
-/**
- * A sub class used for normal async invoke.
- *
- * <b>NOTICE!!</b>
- *
- * <p>
- * You should never rely on this class directly when using or extending Dubbo, the implementation of {@link SimpleAsyncRpcResult}
- * is only a workaround for compatibility purpose. It may be changed or even get removed from the next major version.
- * Please only use {@link Result} or {@link RpcResult}.
- * </p>
- *
- * Check {@link AsyncRpcResult} for more details.
- *
- * TODO AsyncRpcResult, AsyncNormalRpcResult should not be a parent-child hierarchy.
- */
-public class SimpleAsyncRpcResult extends AsyncRpcResult {
-    public SimpleAsyncRpcResult(CompletableFuture<Object> future, boolean registerCallback) {
-        super(future, registerCallback);
-    }
-
-    public SimpleAsyncRpcResult(CompletableFuture<Object> future, CompletableFuture<Result> rFuture, boolean registerCallback) {
-        super(future, rFuture, registerCallback);
-    }
-
-    @Override
-    public Object recreate() throws Throwable {
-        // TODO should we check the status of valueFuture here?
-        return null;
-    }
-}

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/ActiveLimitFilter.java

@@ -19,14 +19,17 @@ package org.apache.dubbo.rpc.filter;
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.extension.Activate;
+import org.apache.dubbo.common.utils.StringUtils;
 import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcStatus;
 
 /**
+ *
  * ActiveLimitFilter restrict the concurrent client invocation for a service or service's method from client side.
  * To use active limit filter, configured url with <b>actives</b> and provide valid >0 integer value.
  * <pre>
@@ -39,50 +42,75 @@ import org.apache.dubbo.rpc.RpcStatus;
  * @see Filter
  */
 @Activate(group = Constants.CONSUMER, value = Constants.ACTIVES_KEY)
-public class ActiveLimitFilter implements Filter {
+public class ActiveLimitFilter extends ListenableFilter {
+
+    private static final String ACTIVELIMIT_FILTER_START_TIME = "activelimit_filter_start_time";
+
+    public ActiveLimitFilter() {
+        super.listener = new ActiveLimitListener();
+    }
 
     @Override
     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
         URL url = invoker.getUrl();
         String methodName = invocation.getMethodName();
         int max = invoker.getUrl().getMethodParameter(methodName, Constants.ACTIVES_KEY, 0);
-        RpcStatus count = RpcStatus.getStatus(invoker.getUrl(), invocation.getMethodName());
-        if (!count.beginCount(url, methodName, max)) {
+        RpcStatus rpcStatus = RpcStatus.getStatus(invoker.getUrl(), invocation.getMethodName());
+        if (!RpcStatus.beginCount(url, methodName, max)) {
             long timeout = invoker.getUrl().getMethodParameter(invocation.getMethodName(), Constants.TIMEOUT_KEY, 0);
             long start = System.currentTimeMillis();
             long remain = timeout;
-            synchronized (count) {
-                while (!count.beginCount(url, methodName, max)) {
+            synchronized (rpcStatus) {
+                while (!RpcStatus.beginCount(url, methodName, max)) {
                     try {
-                        count.wait(remain);
+                        rpcStatus.wait(remain);
                     } catch (InterruptedException e) {
                         // ignore
                     }
                     long elapsed = System.currentTimeMillis() - start;
                     remain = timeout - elapsed;
                     if (remain <= 0) {
-                        throw new RpcException("Waiting concurrent invoke timeout in client-side for service:  "
-                                + invoker.getInterface().getName() + ", method: "
-                                + invocation.getMethodName() + ", elapsed: " + elapsed
-                                + ", timeout: " + timeout + ". concurrent invokes: " + count.getActive()
-                                + ". max concurrent invoke limit: " + max);
+                        throw new RpcException("Waiting concurrent invoke timeout in client-side for service:  " + invoker.getInterface().getName() + ", method: " + invocation.getMethodName() + ", elapsed: " + elapsed + ", timeout: " + timeout + ". concurrent invokes: " + rpcStatus.getActive() + ". max concurrent invoke limit: " + max);
                     }
                 }
             }
         }
 
-        boolean isSuccess = true;
-        long begin = System.currentTimeMillis();
-        try {
-            return invoker.invoke(invocation);
-        } catch (RuntimeException t) {
-            isSuccess = false;
-            throw t;
-        } finally {
-            count.endCount(url, methodName, System.currentTimeMillis() - begin, isSuccess);
+        invocation.setAttachment(ACTIVELIMIT_FILTER_START_TIME, String.valueOf(System.currentTimeMillis()));
+
+        return invoker.invoke(invocation);
+    }
+
+    static class ActiveLimitListener implements Listener {
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
+            String methodName = invocation.getMethodName();
+            URL url = invoker.getUrl();
+            int max = invoker.getUrl().getMethodParameter(methodName, Constants.ACTIVES_KEY, 0);
+
+            RpcStatus.endCount(url, methodName, getElapsed(invocation), true);
+            notifyFinish(RpcStatus.getStatus(url, methodName), max);
+        }
+
+        @Override
+        public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
+            String methodName = invocation.getMethodName();
+            URL url = invoker.getUrl();
+            int max = invoker.getUrl().getMethodParameter(methodName, Constants.ACTIVES_KEY, 0);
+
+            RpcStatus.endCount(url, methodName, getElapsed(invocation), false);
+            notifyFinish(RpcStatus.getStatus(url, methodName), max);
+        }
+
+        private long getElapsed(Invocation invocation) {
+            String beginTime = invocation.getAttachment(ACTIVELIMIT_FILTER_START_TIME);
+            return StringUtils.isNotEmpty(beginTime) ? System.currentTimeMillis() - Long.parseLong(beginTime) : 0;
+        }
+
+        private void notifyFinish(RpcStatus rpcStatus, int max) {
             if (max > 0) {
-                synchronized (count) {
-                    count.notifyAll();
+                synchronized (rpcStatus) {
+                    rpcStatus.notifyAll();
                 }
             }
         }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/CompatibleFilter.java

@@ -24,9 +24,9 @@ import org.apache.dubbo.common.utils.PojoUtils;
 import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
-import org.apache.dubbo.rpc.RpcResult;
 
 import java.lang.reflect.Method;
 import java.lang.reflect.Type;
@@ -45,44 +45,54 @@ import java.lang.reflect.Type;
  * @see Filter
  *
  */
-public class CompatibleFilter implements Filter {
+public class CompatibleFilter extends ListenableFilter {
 
     private static Logger logger = LoggerFactory.getLogger(CompatibleFilter.class);
 
+    public CompatibleFilter() {
+        super.listener = new CompatibleListener();
+    }
+
     @Override
     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
-        Result result = invoker.invoke(invocation);
-        if (!invocation.getMethodName().startsWith("$") && !result.hasException()) {
-            Object value = result.getValue();
-            if (value != null) {
-                try {
-                    Method method = invoker.getInterface().getMethod(invocation.getMethodName(), invocation.getParameterTypes());
-                    Class<?> type = method.getReturnType();
-                    Object newValue;
-                    String serialization = invoker.getUrl().getParameter(Constants.SERIALIZATION_KEY);
-                    if ("json".equals(serialization)
-                            || "fastjson".equals(serialization)) {
-                        // If the serialization key is json or fastjson
-                        Type gtype = method.getGenericReturnType();
-                        newValue = PojoUtils.realize(value, type, gtype);
-                    } else if (!type.isInstance(value)) {
-                        //if local service interface's method's return type is not instance of return value
-                        newValue = PojoUtils.isPojo(type)
-                                ? PojoUtils.realize(value, type)
-                                : CompatibleTypeUtils.compatibleTypeConvert(value, type);
+        return invoker.invoke(invocation);
+    }
 
-                    } else {
-                        newValue = value;
+    static class CompatibleListener implements Listener {
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
+            if (!invocation.getMethodName().startsWith("$") && !result.hasException()) {
+                Object value = result.getValue();
+                if (value != null) {
+                    try {
+                        Method method = invoker.getInterface().getMethod(invocation.getMethodName(), invocation.getParameterTypes());
+                        Class<?> type = method.getReturnType();
+                        Object newValue;
+                        String serialization = invoker.getUrl().getParameter(Constants.SERIALIZATION_KEY);
+                        if ("json".equals(serialization) || "fastjson".equals(serialization)) {
+                            // If the serialization key is json or fastjson
+                            Type gtype = method.getGenericReturnType();
+                            newValue = PojoUtils.realize(value, type, gtype);
+                        } else if (!type.isInstance(value)) {
+                            //if local service interface's method's return type is not instance of return value
+                            newValue = PojoUtils.isPojo(type) ? PojoUtils.realize(value, type) : CompatibleTypeUtils.compatibleTypeConvert(value, type);
+
+                        } else {
+                            newValue = value;
+                        }
+                        if (newValue != value) {
+                            result.setValue(newValue);
+                        }
+                    } catch (Throwable t) {
+                        logger.warn(t.getMessage(), t);
                     }
-                    if (newValue != value) {
-                        result = new RpcResult(newValue);
-                    }
-                } catch (Throwable t) {
-                    logger.warn(t.getMessage(), t);
                 }
             }
         }
-        return result;
-    }
 
+        @Override
+        public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
+
+        }
+    }
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/ConsumerContextFilter.java

@@ -19,9 +19,9 @@ package org.apache.dubbo.rpc.filter;
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.extension.Activate;
 import org.apache.dubbo.common.utils.NetUtils;
-import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
@@ -35,7 +35,11 @@ import org.apache.dubbo.rpc.RpcInvocation;
  * @see RpcContext
  */
 @Activate(group = Constants.CONSUMER, order = -10000)
-public class ConsumerContextFilter implements Filter {
+public class ConsumerContextFilter extends ListenableFilter {
+
+    public ConsumerContextFilter() {
+        super.listener = new ConsumerContextListener();
+    }
 
     @Override
     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
@@ -49,18 +53,22 @@ public class ConsumerContextFilter implements Filter {
             ((RpcInvocation) invocation).setInvoker(invoker);
         }
         try {
-            // TODO should we clear server context?
             RpcContext.removeServerContext();
             return invoker.invoke(invocation);
         } finally {
-            // TODO removeContext? but we need to save future for RpcContext.getFuture() API. If clear attachments here, attachments will not available when postProcessResult is invoked.
-            RpcContext.getContext().clearAttachments();
+            RpcContext.removeContext();
         }
     }
 
-    @Override
-    public Result onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
-        RpcContext.getServerContext().setAttachments(result.getAttachments());
-        return result;
+    static class ConsumerContextListener implements Listener {
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
+            RpcContext.getServerContext().setAttachments(result.getAttachments());
+        }
+
+        @Override
+        public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
+
+        }
     }
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/ContextFilter.java

@@ -18,9 +18,9 @@ package org.apache.dubbo.rpc.filter;
 
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.extension.Activate;
-import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
@@ -36,7 +36,11 @@ import java.util.Map;
  * @see RpcContext
  */
 @Activate(group = Constants.PROVIDER, order = -10000)
-public class ContextFilter implements Filter {
+public class ContextFilter extends ListenableFilter {
+
+    public ContextFilter() {
+        super.listener = new ContextListener();
+    }
 
     @Override
     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
@@ -84,10 +88,16 @@ public class ContextFilter implements Filter {
         }
     }
 
-    @Override
-    public Result onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
-        // pass attachments to result
-        result.addAttachments(RpcContext.getServerContext().getAttachments());
-        return result;
+    static class ContextListener implements Listener {
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
+            // pass attachments to result
+            result.addAttachments(RpcContext.getServerContext().getAttachments());
+        }
+
+        @Override
+        public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
+
+        }
     }
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/EchoFilter.java

@@ -18,12 +18,12 @@ package org.apache.dubbo.rpc.filter;
 
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.extension.Activate;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
-import org.apache.dubbo.rpc.RpcResult;
 
 /**
  * Dubbo provided default Echo echo service, which is available for all dubbo provider service interface.
@@ -34,7 +34,7 @@ public class EchoFilter implements Filter {
     @Override
     public Result invoke(Invoker<?> invoker, Invocation inv) throws RpcException {
         if (inv.getMethodName().equals(Constants.$ECHO) && inv.getArguments() != null && inv.getArguments().length == 1) {
-            return new RpcResult(inv.getArguments()[0]);
+            return AsyncRpcResult.newDefaultAsyncResult(inv.getArguments()[0], inv);
         }
         return invoker.invoke(inv);
     }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/ExceptionFilter.java

@@ -22,13 +22,12 @@ import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.common.utils.ReflectUtils;
 import org.apache.dubbo.common.utils.StringUtils;
-import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.service.GenericService;
 
 import java.lang.reflect.Method;
@@ -45,85 +44,82 @@ import java.lang.reflect.Method;
  * </ol>
  */
 @Activate(group = Constants.PROVIDER)
-public class ExceptionFilter implements Filter {
-
-    private final Logger logger;
+public class ExceptionFilter extends ListenableFilter {
 
     public ExceptionFilter() {
-        this(LoggerFactory.getLogger(ExceptionFilter.class));
-    }
-
-    public ExceptionFilter(Logger logger) {
-        this.logger = logger;
+        super.listener = new ExceptionListener();
     }
 
     @Override
     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
-        try {
-            return invoker.invoke(invocation);
-        } catch (RuntimeException e) {
-            logger.error("Got unchecked and undeclared exception which called by " + RpcContext.getContext().getRemoteHost()
-                    + ". service: " + invoker.getInterface().getName() + ", method: " + invocation.getMethodName()
-                    + ", exception: " + e.getClass().getName() + ": " + e.getMessage(), e);
-            throw e;
-        }
+        return invoker.invoke(invocation);
     }
 
-    @Override
-    public Result onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
-        if (result.hasException() && GenericService.class != invoker.getInterface()) {
-            try {
-                Throwable exception = result.getException();
+    static class ExceptionListener implements Listener {
 
-                // directly throw if it's checked exception
-                if (!(exception instanceof RuntimeException) && (exception instanceof Exception)) {
-                    return result;
-                }
-                // directly throw if the exception appears in the signature
+        private Logger logger = LoggerFactory.getLogger(ExceptionListener.class);
+
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
+            if (result.hasException() && GenericService.class != invoker.getInterface()) {
                 try {
-                    Method method = invoker.getInterface().getMethod(invocation.getMethodName(), invocation.getParameterTypes());
-                    Class<?>[] exceptionClassses = method.getExceptionTypes();
-                    for (Class<?> exceptionClass : exceptionClassses) {
-                        if (exception.getClass().equals(exceptionClass)) {
-                            return result;
-                        }
+                    Throwable exception = result.getException();
+
+                    // directly throw if it's checked exception
+                    if (!(exception instanceof RuntimeException) && (exception instanceof Exception)) {
+                        return;
+                    }
+                    // directly throw if the exception appears in the signature
+                    try {
+                        Method method = invoker.getInterface().getMethod(invocation.getMethodName(), invocation.getParameterTypes());
+                        Class<?>[] exceptionClassses = method.getExceptionTypes();
+                        for (Class<?> exceptionClass : exceptionClassses) {
+                            if (exception.getClass().equals(exceptionClass)) {
+                                return;
+                            }
+                        }
+                    } catch (NoSuchMethodException e) {
+                        return;
                     }
-                } catch (NoSuchMethodException e) {
-                    return result;
-                }
 
-                // for the exception not found in method's signature, print ERROR message in server's log.
-                logger.error("Got unchecked and undeclared exception which called by " + RpcContext.getContext().getRemoteHost()
-                        + ". service: " + invoker.getInterface().getName() + ", method: " + invocation.getMethodName()
-                        + ", exception: " + exception.getClass().getName() + ": " + exception.getMessage(), exception);
+                    // for the exception not found in method's signature, print ERROR message in server's log.
+                    logger.error("Got unchecked and undeclared exception which called by " + RpcContext.getContext().getRemoteHost() + ". service: " + invoker.getInterface().getName() + ", method: " + invocation.getMethodName() + ", exception: " + exception.getClass().getName() + ": " + exception.getMessage(), exception);
 
-                // directly throw if exception class and interface class are in the same jar file.
-                String serviceFile = ReflectUtils.getCodeBase(invoker.getInterface());
-                String exceptionFile = ReflectUtils.getCodeBase(exception.getClass());
-                if (serviceFile == null || exceptionFile == null || serviceFile.equals(exceptionFile)) {
-                    return result;
-                }
-                // directly throw if it's JDK exception
-                String className = exception.getClass().getName();
-                if (className.startsWith("java.") || className.startsWith("javax.")) {
-                    return result;
-                }
-                // directly throw if it's dubbo exception
-                if (exception instanceof RpcException) {
-                    return result;
-                }
+                    // directly throw if exception class and interface class are in the same jar file.
+                    String serviceFile = ReflectUtils.getCodeBase(invoker.getInterface());
+                    String exceptionFile = ReflectUtils.getCodeBase(exception.getClass());
+                    if (serviceFile == null || exceptionFile == null || serviceFile.equals(exceptionFile)) {
+                        return;
+                    }
+                    // directly throw if it's JDK exception
+                    String className = exception.getClass().getName();
+                    if (className.startsWith("java.") || className.startsWith("javax.")) {
+                        return;
+                    }
+                    // directly throw if it's dubbo exception
+                    if (exception instanceof RpcException) {
+                        return;
+                    }
 
-                // otherwise, wrap with RuntimeException and throw back to the client
-                return new RpcResult(new RuntimeException(StringUtils.toString(exception)));
-            } catch (Throwable e) {
-                logger.warn("Fail to ExceptionFilter when called by " + RpcContext.getContext().getRemoteHost()
-                        + ". service: " + invoker.getInterface().getName() + ", method: " + invocation.getMethodName()
-                        + ", exception: " + e.getClass().getName() + ": " + e.getMessage(), e);
-                return result;
+                    // otherwise, wrap with RuntimeException and throw back to the client
+                    result.setException(new RuntimeException(StringUtils.toString(exception)));
+                    return;
+                } catch (Throwable e) {
+                    logger.warn("Fail to ExceptionFilter when called by " + RpcContext.getContext().getRemoteHost() + ". service: " + invoker.getInterface().getName() + ", method: " + invocation.getMethodName() + ", exception: " + e.getClass().getName() + ": " + e.getMessage(), e);
+                    return;
+                }
             }
         }
-        return result;
-    }
 
+        @Override
+        public void onError(Throwable e, Invoker<?> invoker, Invocation invocation) {
+            logger.error("Got unchecked and undeclared exception which called by " + RpcContext.getContext().getRemoteHost() + ". service: " + invoker.getInterface().getName() + ", method: " + invocation.getMethodName() + ", exception: " + e.getClass().getName() + ": " + e.getMessage(), e);
+        }
+
+        // For test purpose
+        public void setLogger(Logger logger) {
+            this.logger = logger;
+        }
+    }
 }
 

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/ExecuteLimitFilter.java

@@ -19,21 +19,29 @@ package org.apache.dubbo.rpc.filter;
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.extension.Activate;
-import org.apache.dubbo.rpc.Filter;
+import org.apache.dubbo.common.utils.StringUtils;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcStatus;
 
 /**
+ *
  * The maximum parallel execution request count per method per service for the provider.If the max configured
  * <b>executes</b> is set to 10 and if invoke request where it is already 10 then it will throws exception. It
  * continue the same behaviour un till it is <10.
  *
  */
 @Activate(group = Constants.PROVIDER, value = Constants.EXECUTES_KEY)
-public class ExecuteLimitFilter implements Filter {
+public class ExecuteLimitFilter extends ListenableFilter {
+
+    private static final String EXECUTELIMIT_FILTER_START_TIME = "execugtelimit_filter_start_time";
+
+    public ExecuteLimitFilter() {
+        super.listener = new ExecuteLimitListener();
+    }
 
     @Override
     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
@@ -46,20 +54,32 @@ public class ExecuteLimitFilter implements Filter {
                     "\" /> limited.");
         }
 
-        long begin = System.currentTimeMillis();
-        boolean isSuccess = true;
+        invocation.setAttachment(EXECUTELIMIT_FILTER_START_TIME, String.valueOf(System.currentTimeMillis()));
         try {
             return invoker.invoke(invocation);
         } catch (Throwable t) {
-            isSuccess = false;
             if (t instanceof RuntimeException) {
                 throw (RuntimeException) t;
             } else {
                 throw new RpcException("unexpected exception when ExecuteLimitFilter", t);
             }
-        } finally {
-            RpcStatus.endCount(url, methodName, System.currentTimeMillis() - begin, isSuccess);
         }
     }
 
+    static class ExecuteLimitListener implements Listener {
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
+            RpcStatus.endCount(invoker.getUrl(), invocation.getMethodName(), getElapsed(invocation), true);
+        }
+
+        @Override
+        public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
+            RpcStatus.endCount(invoker.getUrl(), invocation.getMethodName(), getElapsed(invocation), false);
+        }
+
+        private long getElapsed(Invocation invocation) {
+            String beginTime = invocation.getAttachment(EXECUTELIMIT_FILTER_START_TIME);
+            return StringUtils.isNotEmpty(beginTime) ? System.currentTimeMillis() - Long.parseLong(beginTime) : 0;
+        }
+    }
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/GenericFilter.java

@@ -28,14 +28,13 @@ import org.apache.dubbo.common.serialize.Serialization;
 import org.apache.dubbo.common.utils.PojoUtils;
 import org.apache.dubbo.common.utils.ReflectUtils;
 import org.apache.dubbo.common.utils.StringUtils;
-import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.service.GenericException;
 import org.apache.dubbo.rpc.service.GenericService;
 import org.apache.dubbo.rpc.support.ProtocolUtils;
@@ -47,11 +46,15 @@ import java.lang.reflect.Method;
  * GenericInvokerFilter.
  */
 @Activate(group = Constants.PROVIDER, order = -20000)
-public class GenericFilter implements Filter {
+public class GenericFilter extends ListenableFilter {
+
+    public GenericFilter() {
+        super.listener = new GenericListener();
+    }
 
     @Override
     public Result invoke(Invoker<?> invoker, Invocation inv) throws RpcException {
-        if (inv.getMethodName().equals(Constants.$INVOKE)
+        if ((inv.getMethodName().equals(Constants.$INVOKE) || inv.getMethodName().equals(Constants.$INVOKE_ASYNC))
                 && inv.getArguments() != null
                 && inv.getArguments().length == 3
                 && !GenericService.class.isAssignableFrom(invoker.getInterface())) {
@@ -108,26 +111,7 @@ public class GenericFilter implements Filter {
                         }
                     }
                 }
-                Result result = invoker.invoke(new RpcInvocation(method, args, inv.getAttachments()));
-                if (result.hasException()
-                        && !(result.getException() instanceof GenericException)) {
-                    return new RpcResult(new GenericException(result.getException()));
-                }
-                if (ProtocolUtils.isJavaGenericSerialization(generic)) {
-                    try {
-                        UnsafeByteArrayOutputStream os = new UnsafeByteArrayOutputStream(512);
-                        ExtensionLoader.getExtensionLoader(Serialization.class)
-                                .getExtension(Constants.GENERIC_SERIALIZATION_NATIVE_JAVA)
-                                .serialize(null, os).writeObject(result.getValue());
-                        return new RpcResult(os.toByteArray());
-                    } catch (IOException e) {
-                        throw new RpcException("Serialize result failed.", e);
-                    }
-                } else if (ProtocolUtils.isBeanGenericSerialization(generic)) {
-                    return new RpcResult(JavaBeanSerializeUtil.serialize(result.getValue(), JavaBeanAccessor.METHOD));
-                } else {
-                    return new RpcResult(PojoUtils.generalize(result.getValue()));
-                }
+                return invoker.invoke(new RpcInvocation(method, args, inv.getAttachments()));
             } catch (NoSuchMethodException e) {
                 throw new RpcException(e.getMessage(), e);
             } catch (ClassNotFoundException e) {
@@ -137,4 +121,42 @@ public class GenericFilter implements Filter {
         return invoker.invoke(inv);
     }
 
+    static class GenericListener implements Listener {
+
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation inv) {
+            if ((inv.getMethodName().equals(Constants.$INVOKE) || inv.getMethodName().equals(Constants.$INVOKE_ASYNC))
+                    && inv.getArguments() != null
+                    && inv.getArguments().length == 3
+                    && !GenericService.class.isAssignableFrom(invoker.getInterface())) {
+
+                String generic = inv.getAttachment(Constants.GENERIC_KEY);
+                if (StringUtils.isBlank(generic)) {
+                    generic = RpcContext.getContext().getAttachment(Constants.GENERIC_KEY);
+                }
+
+                if (result.hasException() && !(result.getException() instanceof GenericException)) {
+                    result.setException(new GenericException(result.getException()));
+                }
+                if (ProtocolUtils.isJavaGenericSerialization(generic)) {
+                    try {
+                        UnsafeByteArrayOutputStream os = new UnsafeByteArrayOutputStream(512);
+                        ExtensionLoader.getExtensionLoader(Serialization.class).getExtension(Constants.GENERIC_SERIALIZATION_NATIVE_JAVA).serialize(null, os).writeObject(result.getValue());
+                        result.setValue(os.toByteArray());
+                    } catch (IOException e) {
+                        throw new RpcException("Serialize result failed.", e);
+                    }
+                } else if (ProtocolUtils.isBeanGenericSerialization(generic)) {
+                    result.setValue(JavaBeanSerializeUtil.serialize(result.getValue(), JavaBeanAccessor.METHOD));
+                } else {
+                    result.setValue(PojoUtils.generalize(result.getValue()));
+                }
+            }
+        }
+
+        @Override
+        public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
+
+        }
+    }
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/GenericImplFilter.java

@@ -25,37 +25,42 @@ import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.common.utils.PojoUtils;
 import org.apache.dubbo.common.utils.ReflectUtils;
-import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.service.GenericException;
 import org.apache.dubbo.rpc.support.ProtocolUtils;
+import org.apache.dubbo.rpc.support.RpcUtils;
 
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
+import java.lang.reflect.Type;
 
 /**
  * GenericImplInvokerFilter
  */
 @Activate(group = Constants.CONSUMER, value = Constants.GENERIC_KEY, order = 20000)
-public class GenericImplFilter implements Filter {
+public class GenericImplFilter extends ListenableFilter {
 
     private static final Logger logger = LoggerFactory.getLogger(GenericImplFilter.class);
 
     private static final Class<?>[] GENERIC_PARAMETER_TYPES = new Class<?>[]{String.class, String[].class, Object[].class};
 
+    public GenericImplFilter() {
+        super.listener = new GenericImplListener();
+    }
+
     @Override
     public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
         String generic = invoker.getUrl().getParameter(Constants.GENERIC_KEY);
         if (ProtocolUtils.isGeneric(generic)
-                && !Constants.$INVOKE.equals(invocation.getMethodName())
+                && (!Constants.$INVOKE.equals(invocation.getMethodName()) && !Constants.$INVOKE_ASYNC.equals(invocation.getMethodName()))
                 && invocation instanceof RpcInvocation) {
-            RpcInvocation invocation2 = (RpcInvocation) invocation;
+            RpcInvocation invocation2 = new RpcInvocation(invocation);
             String methodName = invocation2.getMethodName();
             Class<?>[] parameterTypes = invocation2.getParameterTypes();
             Object[] arguments = invocation2.getArguments();
@@ -75,77 +80,15 @@ public class GenericImplFilter implements Filter {
                 args = PojoUtils.generalize(arguments);
             }
 
-            invocation2.setMethodName(Constants.$INVOKE);
+            if (RpcUtils.isReturnTypeFuture(invocation)) {
+                invocation2.setMethodName(Constants.$INVOKE_ASYNC);
+            } else {
+                invocation2.setMethodName(Constants.$INVOKE);
+            }
             invocation2.setParameterTypes(GENERIC_PARAMETER_TYPES);
             invocation2.setArguments(new Object[]{methodName, types, args});
-            Result result = invoker.invoke(invocation2);
-
-            if (!result.hasException()) {
-                Object value = result.getValue();
-                try {
-                    Method method = invoker.getInterface().getMethod(methodName, parameterTypes);
-                    if (ProtocolUtils.isBeanGenericSerialization(generic)) {
-                        if (value == null) {
-                            return new RpcResult(value);
-                        } else if (value instanceof JavaBeanDescriptor) {
-                            return new RpcResult(JavaBeanSerializeUtil.deserialize((JavaBeanDescriptor) value));
-                        } else {
-                            throw new RpcException(
-                                    "The type of result value is " +
-                                            value.getClass().getName() +
-                                            " other than " +
-                                            JavaBeanDescriptor.class.getName() +
-                                            ", and the result is " +
-                                            value);
-                        }
-                    } else {
-                        return new RpcResult(PojoUtils.realize(value, method.getReturnType(), method.getGenericReturnType()));
-                    }
-                } catch (NoSuchMethodException e) {
-                    throw new RpcException(e.getMessage(), e);
-                }
-            } else if (result.getException() instanceof GenericException) {
-                GenericException exception = (GenericException) result.getException();
-                try {
-                    String className = exception.getExceptionClass();
-                    Class<?> clazz = ReflectUtils.forName(className);
-                    Throwable targetException = null;
-                    Throwable lastException = null;
-                    try {
-                        targetException = (Throwable) clazz.newInstance();
-                    } catch (Throwable e) {
-                        lastException = e;
-                        for (Constructor<?> constructor : clazz.getConstructors()) {
-                            try {
-                                targetException = (Throwable) constructor.newInstance(new Object[constructor.getParameterTypes().length]);
-                                break;
-                            } catch (Throwable e1) {
-                                lastException = e1;
-                            }
-                        }
-                    }
-                    if (targetException != null) {
-                        try {
-                            Field field = Throwable.class.getDeclaredField("detailMessage");
-                            if (!field.isAccessible()) {
-                                field.setAccessible(true);
-                            }
-                            field.set(targetException, exception.getExceptionMessage());
-                        } catch (Throwable e) {
-                            logger.warn(e.getMessage(), e);
-                        }
-                        result = new RpcResult(targetException);
-                    } else if (lastException != null) {
-                        throw lastException;
-                    }
-                } catch (Throwable e) {
-                    throw new RpcException("Can not deserialize exception " + exception.getExceptionClass() + ", message: " + exception.getExceptionMessage(), e);
-                }
-            }
-            return result;
-        }
-
-        if (invocation.getMethodName().equals(Constants.$INVOKE)
+            return invoker.invoke(invocation2);
+        } else if ((invocation.getMethodName().equals(Constants.$INVOKE) || invocation.getMethodName().equals(Constants.$INVOKE_ASYNC))
                 && invocation.getArguments() != null
                 && invocation.getArguments().length == 3
                 && ProtocolUtils.isGeneric(generic)) {
@@ -166,20 +109,89 @@ public class GenericImplFilter implements Filter {
                 }
             }
 
-            ((RpcInvocation) invocation).setAttachment(
+            invocation.setAttachment(
                     Constants.GENERIC_KEY, invoker.getUrl().getParameter(Constants.GENERIC_KEY));
         }
         return invoker.invoke(invocation);
     }
 
     private void error(String generic, String expected, String actual) throws RpcException {
-        throw new RpcException(
-                "Generic serialization [" +
-                        generic +
-                        "] only support message type " +
-                        expected +
-                        " and your message type is " +
-                        actual);
+        throw new RpcException("Generic serialization [" + generic + "] only support message type " + expected + " and your message type is " + actual);
+    }
+
+    static class GenericImplListener implements Listener {
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
+            String generic = invoker.getUrl().getParameter(Constants.GENERIC_KEY);
+            String methodName = invocation.getMethodName();
+            Class<?>[] parameterTypes = invocation.getParameterTypes();
+            if (ProtocolUtils.isGeneric(generic)
+                    && (!Constants.$INVOKE.equals(invocation.getMethodName()) && !Constants.$INVOKE_ASYNC.equals(invocation.getMethodName()))
+                    && invocation instanceof RpcInvocation) {
+                if (!result.hasException()) {
+                    Object value = result.getValue();
+                    try {
+                        Method method = invoker.getInterface().getMethod(methodName, parameterTypes);
+                        if (ProtocolUtils.isBeanGenericSerialization(generic)) {
+                            if (value == null) {
+                                result.setValue(value);
+                            } else if (value instanceof JavaBeanDescriptor) {
+                                result.setValue(JavaBeanSerializeUtil.deserialize((JavaBeanDescriptor) value));
+                            } else {
+                                throw new RpcException("The type of result value is " + value.getClass().getName() + " other than " + JavaBeanDescriptor.class.getName() + ", and the result is " + value);
+                            }
+                        } else {
+                            Type[] types = ReflectUtils.getReturnTypes(method);
+                            result.setValue(PojoUtils.realize(value, (Class<?>) types[0], types[1]));
+                        }
+                    } catch (NoSuchMethodException e) {
+                        throw new RpcException(e.getMessage(), e);
+                    }
+                } else if (result.getException() instanceof GenericException) {
+                    GenericException exception = (GenericException) result.getException();
+                    try {
+                        String className = exception.getExceptionClass();
+                        Class<?> clazz = ReflectUtils.forName(className);
+                        Throwable targetException = null;
+                        Throwable lastException = null;
+                        try {
+                            targetException = (Throwable) clazz.newInstance();
+                        } catch (Throwable e) {
+                            lastException = e;
+                            for (Constructor<?> constructor : clazz.getConstructors()) {
+                                try {
+                                    targetException = (Throwable) constructor.newInstance(new Object[constructor.getParameterTypes().length]);
+                                    break;
+                                } catch (Throwable e1) {
+                                    lastException = e1;
+                                }
+                            }
+                        }
+                        if (targetException != null) {
+                            try {
+                                Field field = Throwable.class.getDeclaredField("detailMessage");
+                                if (!field.isAccessible()) {
+                                    field.setAccessible(true);
+                                }
+                                field.set(targetException, exception.getExceptionMessage());
+                            } catch (Throwable e) {
+                                logger.warn(e.getMessage(), e);
+                            }
+                            result.setException(targetException);
+                        } else if (lastException != null) {
+                            throw lastException;
+                        }
+                    } catch (Throwable e) {
+                        throw new RpcException("Can not deserialize exception " + exception.getExceptionClass() + ", message: " + exception.getExceptionMessage(), e);
+                    }
+                }
+            }
+        }
+
+        @Override
+        public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
+
+        }
     }
 
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/filter/TimeoutFilter.java

@@ -20,12 +20,11 @@ import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.extension.Activate;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
-import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
-import org.apache.dubbo.rpc.RpcInvocation;
 
 import java.util.Arrays;
 
@@ -33,42 +32,40 @@ import java.util.Arrays;
  * Log any invocation timeout, but don't stop server from running
  */
 @Activate(group = Constants.PROVIDER)
-public class TimeoutFilter implements Filter {
+public class TimeoutFilter extends ListenableFilter {
 
     private static final Logger logger = LoggerFactory.getLogger(TimeoutFilter.class);
 
     private static final String TIMEOUT_FILTER_START_TIME = "timeout_filter_start_time";
 
-    @Override
-    public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
-        if (invocation.getAttachments() != null) {
-            long start = System.currentTimeMillis();
-            invocation.getAttachments().put(TIMEOUT_FILTER_START_TIME, String.valueOf(start));
-        } else {
-            if (invocation instanceof RpcInvocation) {
-                RpcInvocation invc = (RpcInvocation) invocation;
-                long start = System.currentTimeMillis();
-                invc.setAttachment(TIMEOUT_FILTER_START_TIME, String.valueOf(start));
-            }
-        }
-        return invoker.invoke(invocation);
+    public TimeoutFilter() {
+        super.listener = new TimeoutListener();
     }
 
     @Override
-    public Result onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
-        String startAttach = invocation.getAttachment(TIMEOUT_FILTER_START_TIME);
-        if (startAttach != null) {
-            long elapsed = System.currentTimeMillis() - Long.valueOf(startAttach);
-            if (invoker.getUrl() != null
-                    && elapsed > invoker.getUrl().getMethodParameter(invocation.getMethodName(),
-                    "timeout", Integer.MAX_VALUE)) {
-                if (logger.isWarnEnabled()) {
-                    logger.warn("invoke time out. method: " + invocation.getMethodName()
-                            + " arguments: " + Arrays.toString(invocation.getArguments()) + " , url is "
-                            + invoker.getUrl() + ", invoke elapsed " + elapsed + " ms.");
+    public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
+        invocation.setAttachment(TIMEOUT_FILTER_START_TIME, String.valueOf(System.currentTimeMillis()));
+        return invoker.invoke(invocation);
+    }
+
+    static class TimeoutListener implements Listener {
+
+        @Override
+        public void onResponse(Result result, Invoker<?> invoker, Invocation invocation) {
+            String startAttach = invocation.getAttachment(TIMEOUT_FILTER_START_TIME);
+            if (startAttach != null) {
+                long elapsed = System.currentTimeMillis() - Long.valueOf(startAttach);
+                if (invoker.getUrl() != null && elapsed > invoker.getUrl().getMethodParameter(invocation.getMethodName(), "timeout", Integer.MAX_VALUE)) {
+                    if (logger.isWarnEnabled()) {
+                        logger.warn("invoke time out. method: " + invocation.getMethodName() + " arguments: " + Arrays.toString(invocation.getArguments()) + " , url is " + invoker.getUrl() + ", invoke elapsed " + elapsed + " ms.");
+                    }
                 }
             }
         }
-        return result;
+
+        @Override
+        public void onError(Throwable t, Invoker<?> invoker, Invocation invocation) {
+
+        }
     }
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/protocol/AbstractInvoker.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.rpc.protocol;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.Version;
 import org.apache.dubbo.common.logger.Logger;
@@ -24,13 +23,13 @@ import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.common.utils.ArrayUtils;
 import org.apache.dubbo.common.utils.CollectionUtils;
 import org.apache.dubbo.common.utils.NetUtils;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.support.RpcUtils;
 
 import java.lang.reflect.InvocationTargetException;
@@ -148,9 +147,8 @@ public abstract class AbstractInvoker<T> implements Invoker<T> {
              */
             invocation.addAttachments(contextAttachments);
         }
-        if (getUrl().getMethodParameter(invocation.getMethodName(), Constants.ASYNC_KEY, false)) {
-            invocation.setAttachment(Constants.ASYNC_KEY, Boolean.TRUE.toString());
-        }
+
+        invocation.setInvokeMode(RpcUtils.getInvokeMode(url, invocation));
         RpcUtils.attachInvocationIdIfAsync(getUrl(), invocation);
 
         try {
@@ -158,21 +156,21 @@ public abstract class AbstractInvoker<T> implements Invoker<T> {
         } catch (InvocationTargetException e) { // biz exception
             Throwable te = e.getTargetException();
             if (te == null) {
-                return new RpcResult(e);
+                return AsyncRpcResult.newDefaultAsyncResult(null, e, invocation);
             } else {
                 if (te instanceof RpcException) {
                     ((RpcException) te).setCode(RpcException.BIZ_EXCEPTION);
                 }
-                return new RpcResult(te);
+                return AsyncRpcResult.newDefaultAsyncResult(null, te, invocation);
             }
         } catch (RpcException e) {
             if (e.isBiz()) {
-                return new RpcResult(e);
+                return AsyncRpcResult.newDefaultAsyncResult(null, e, invocation);
             } else {
                 throw e;
             }
         } catch (Throwable e) {
-            return new RpcResult(e);
+            return AsyncRpcResult.newDefaultAsyncResult(null, e, invocation);
         }
     }
 

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/protocol/AbstractProtocol.java

@@ -24,6 +24,7 @@ import org.apache.dubbo.common.utils.ConcurrentHashSet;
 import org.apache.dubbo.rpc.Exporter;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Protocol;
+import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.support.ProtocolUtils;
 
 import java.util.ArrayList;
@@ -82,4 +83,11 @@ public abstract class AbstractProtocol implements Protocol {
             }
         }
     }
+
+    @Override
+    public <T> Invoker<T> refer(Class<T> type, URL url) throws RpcException {
+        return new AsyncToSyncInvoker<>(doRefer(type, url));
+    }
+
+    protected abstract <T> Invoker<T> doRefer(Class<T> type, URL url) throws RpcException;
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/protocol/AbstractProxyProtocol.java

@@ -92,13 +92,14 @@ public abstract class AbstractProxyProtocol extends AbstractProtocol {
     }
 
     @Override
-    public <T> Invoker<T> refer(final Class<T> type, final URL url) throws RpcException {
-        final Invoker<T> target = proxyFactory.getInvoker(doRefer(type, url), type, url);
+    public <T> Invoker<T> doRefer(final Class<T> type, final URL url) throws RpcException {
+        final Invoker<T> target = proxyFactory.getInvoker(getFrameworkProxy(type, url), type, url);
         Invoker<T> invoker = new AbstractInvoker<T>(type, url) {
             @Override
             protected Result doInvoke(Invocation invocation) throws Throwable {
                 try {
                     Result result = target.invoke(invocation);
+                    // FIXME result is an AsyncRpcResult instance.
                     Throwable e = result.getException();
                     if (e != null) {
                         for (Class<?> rpcException : rpcExceptions) {
@@ -143,6 +144,6 @@ public abstract class AbstractProxyProtocol extends AbstractProtocol {
 
     protected abstract <T> Runnable doExport(T impl, Class<T> type, URL url) throws RpcException;
 
-    protected abstract <T> T doRefer(Class<T> type, URL url) throws RpcException;
+    protected abstract <T> T getFrameworkProxy(Class<T> type, URL url) throws RpcException;
 
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/protocol/AsyncToSyncInvoker.java

@@ -0,0 +1,89 @@
+/*
+ * 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.protocol;
+
+import org.apache.dubbo.common.URL;
+import org.apache.dubbo.remoting.RemotingException;
+import org.apache.dubbo.remoting.TimeoutException;
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.InvokeMode;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
+import org.apache.dubbo.rpc.RpcException;
+import org.apache.dubbo.rpc.RpcInvocation;
+
+import java.util.concurrent.ExecutionException;
+
+/**
+ * This class will work as a wrapper wrapping outside of each protocol invoker.
+ * @param <T>
+ */
+public class AsyncToSyncInvoker<T> implements Invoker<T> {
+
+    private Invoker<T> invoker;
+
+    public AsyncToSyncInvoker(Invoker<T> invoker) {
+        this.invoker = invoker;
+    }
+
+    @Override
+    public Class<T> getInterface() {
+        return invoker.getInterface();
+    }
+
+    @Override
+    public Result invoke(Invocation invocation) throws RpcException {
+        Result asyncResult = invoker.invoke(invocation);
+
+        try {
+            if (InvokeMode.SYNC == ((RpcInvocation)invocation).getInvokeMode()) {
+                asyncResult.get();
+            }
+        } catch (InterruptedException e) {
+            throw new RpcException("Interrupted unexpectedly while waiting for remoting result to return!  method: " + invocation.getMethodName() + ", provider: " + getUrl() + ", cause: " + e.getMessage(), e);
+        } catch (ExecutionException e) {
+            Throwable t = e.getCause();
+            if (t instanceof TimeoutException) {
+                throw new RpcException(RpcException.TIMEOUT_EXCEPTION, "Invoke remote method timeout. method: " + invocation.getMethodName() + ", provider: " + getUrl() + ", cause: " + e.getMessage(), e);
+            } else if (t instanceof RemotingException) {
+                throw new RpcException(RpcException.NETWORK_EXCEPTION, "Failed to invoke remote method: " + invocation.getMethodName() + ", provider: " + getUrl() + ", cause: " + e.getMessage(), e);
+            }
+        } catch (Throwable e) {
+            throw new RpcException(e.getMessage(), e);
+        }
+        return asyncResult;
+    }
+
+    @Override
+    public URL getUrl() {
+        return invoker.getUrl();
+    }
+
+    @Override
+    public boolean isAvailable() {
+        return invoker.isAvailable();
+    }
+
+    @Override
+    public void destroy() {
+        invoker.destroy();
+    }
+
+    public Invoker<T> getInvoker() {
+        return invoker;
+    }
+}

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/protocol/ProtocolFilterWrapper.java

@@ -19,11 +19,11 @@ package org.apache.dubbo.rpc.protocol;
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.extension.ExtensionLoader;
-import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Exporter;
 import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.ListenableFilter;
 import org.apache.dubbo.rpc.Protocol;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
@@ -70,14 +70,29 @@ public class ProtocolFilterWrapper implements Protocol {
 
                     @Override
                     public Result invoke(Invocation invocation) throws RpcException {
-                        Result result = filter.invoke(next, invocation);
-                        if (result instanceof AsyncRpcResult) {
-                            AsyncRpcResult asyncResult = (AsyncRpcResult) result;
-                            asyncResult.thenApplyWithContext(r -> filter.onResponse(r, invoker, invocation));
-                            return asyncResult;
-                        } else {
-                            return filter.onResponse(result, invoker, invocation);
+                        Result asyncResult;
+                        try {
+                            asyncResult = filter.invoke(next, invocation);
+                        } catch (Exception e) {
+                            // onError callback
+                            if (filter instanceof ListenableFilter) {
+                                Filter.Listener listener = ((ListenableFilter) filter).listener();
+                                if (listener != null) {
+                                    listener.onError(e, invoker, invocation);
+                                }
+                            }
+                            throw e;
                         }
+                        return asyncResult.thenApplyWithContext(r -> {
+                            // onResponse callback
+                            if (filter instanceof ListenableFilter) {
+                                Filter.Listener listener = ((ListenableFilter) filter).listener();
+                                if (listener != null) {
+                                    listener.onResponse(r, invoker, invocation);
+                                }
+                            }
+                            return r;
+                        });
                     }
 
                     @Override

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/proxy/AbstractProxyInvoker.java

@@ -19,6 +19,7 @@ package org.apache.dubbo.rpc.proxy;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.AsyncContextImpl;
 import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
@@ -26,11 +27,11 @@ import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.support.RpcUtils;
 
 import java.lang.reflect.InvocationTargetException;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionException;
 
 /**
  * InvokerWrapper
@@ -78,30 +79,47 @@ public abstract class AbstractProxyInvoker<T> implements Invoker<T> {
     public void destroy() {
     }
 
-    // TODO Unified to AsyncResult?
     @Override
     public Result invoke(Invocation invocation) throws RpcException {
-        RpcContext rpcContext = RpcContext.getContext();
         try {
-            Object obj = doInvoke(proxy, invocation.getMethodName(), invocation.getParameterTypes(), invocation.getArguments());
-            if (RpcUtils.isReturnTypeFuture(invocation)) {
-                return new AsyncRpcResult((CompletableFuture<Object>) obj);
-            } else if (rpcContext.isAsyncStarted()) { // ignore obj in case of RpcContext.startAsync()? always rely on user to write back.
-                return new AsyncRpcResult(((AsyncContextImpl)(rpcContext.getAsyncContext())).getInternalFuture());
-            } else {
-                return new RpcResult(obj);
-            }
+            Object value = doInvoke(proxy, invocation.getMethodName(), invocation.getParameterTypes(), invocation.getArguments());
+            CompletableFuture<Object> future = wrapWithFuture(value, invocation);
+            CompletableFuture<AppResponse> appResponseFuture = future.handle((obj, t) -> {
+                AppResponse result = new AppResponse();
+                if (t != null) {
+                    if (t instanceof CompletionException) {
+                        result.setException(t.getCause());
+                    } else {
+                        result.setException(t);
+                    }
+                } else {
+                    result.setValue(obj);
+                }
+                return result;
+            });
+            return new AsyncRpcResult(appResponseFuture, invocation);
         } catch (InvocationTargetException e) {
-            // TODO async throw exception before async thread write back, should stop asyncContext
-            if (rpcContext.isAsyncStarted() && !rpcContext.stopAsync()) {
+            if (RpcContext.getContext().isAsyncStarted() && !RpcContext.getContext().stopAsync()) {
                 logger.error("Provider async started, but got an exception from the original method, cannot write the exception back to consumer because an async result may have returned the new thread.", e);
             }
-            return new RpcResult(e.getTargetException());
+            return AsyncRpcResult.newDefaultAsyncResult(null, e.getTargetException(), invocation);
         } catch (Throwable e) {
             throw new RpcException("Failed to invoke remote proxy method " + invocation.getMethodName() + " to " + getUrl() + ", cause: " + e.getMessage(), e);
         }
     }
 
+    private CompletableFuture<Object> wrapWithFuture (Object value, Invocation invocation) {
+        if (RpcContext.getContext().isAsyncStarted()) {
+            return ((AsyncContextImpl)(RpcContext.getContext().getAsyncContext())).getInternalFuture();
+        } else if (RpcUtils.isReturnTypeFuture(invocation)) {
+            if (value == null) {
+                return CompletableFuture.completedFuture(null);
+            }
+            return (CompletableFuture<Object>) value;
+        }
+        return CompletableFuture.completedFuture(value);
+    }
+
     protected abstract Object doInvoke(T proxy, String methodName, Class<?>[] parameterTypes, Object[] arguments) throws Throwable;
 
     @Override

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/proxy/InvokerInvocationHandler.java

@@ -16,12 +16,10 @@
  */
 package org.apache.dubbo.rpc.proxy;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.support.RpcUtils;
 
 import java.lang.reflect.InvocationHandler;
 import java.lang.reflect.Method;
@@ -54,16 +52,6 @@ public class InvokerInvocationHandler implements InvocationHandler {
             return invoker.equals(args[0]);
         }
 
-        return invoker.invoke(createInvocation(method, args)).recreate();
+        return invoker.invoke(new RpcInvocation(method, args)).recreate();
     }
-
-    private RpcInvocation createInvocation(Method method, Object[] args) {
-        RpcInvocation invocation = new RpcInvocation(method, args);
-        if (RpcUtils.hasFutureReturnType(method)) {
-            invocation.setAttachment(Constants.FUTURE_RETURNTYPE_KEY, "true");
-            invocation.setAttachment(Constants.ASYNC_KEY, "true");
-        }
-        return invocation;
-    }
-
 }

dubbo-rpc/dubbo-rpc-api/src/main/java/org/apache/dubbo/rpc/service/GenericService.java

@@ -16,6 +16,8 @@
  */
 package org.apache.dubbo.rpc.service;
 
+import java.util.concurrent.CompletableFuture;
+
 /**
  * Generic service interface
  *
@@ -35,4 +37,12 @@ public interface GenericService {
      */
     Object $invoke(String method, String[] parameterTypes, Object[] args) throws GenericException;
 
+    default CompletableFuture<Object> $invokeAsync(String method, String[] parameterTypes, Object[] args) throws GenericException {
+        Object object = $invoke(method, parameterTypes, args);
+        if (object instanceof CompletableFuture) {
+            return (CompletableFuture<Object>) object;
+        }
+        return CompletableFuture.completedFuture(object);
+    }
+
 }

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

@@ -19,18 +19,18 @@ package org.apache.dubbo.rpc.support;
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.extension.ExtensionLoader;
+import org.apache.dubbo.common.utils.ArrayUtils;
 import org.apache.dubbo.common.utils.ConfigUtils;
 import org.apache.dubbo.common.utils.PojoUtils;
 import org.apache.dubbo.common.utils.ReflectUtils;
 import org.apache.dubbo.common.utils.StringUtils;
-import org.apache.dubbo.common.utils.ArrayUtils;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.ProxyFactory;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
-import org.apache.dubbo.rpc.RpcResult;
 
 import com.alibaba.fastjson.JSON;
 
@@ -104,7 +104,7 @@ final public class MockInvoker<T> implements Invoker<T> {
             try {
                 Type[] returnTypes = RpcUtils.getReturnTypes(invocation);
                 Object value = parseMockValue(mock, returnTypes);
-                return new RpcResult(value);
+                return AsyncRpcResult.newDefaultAsyncResult(value, invocation);
             } catch (Exception ew) {
                 throw new RpcException("mock return invoke error. method :" + invocation.getMethodName()
                         + ", mock:" + mock + ", url: " + url, ew);

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

@@ -38,7 +38,7 @@ final public class MockProtocol extends AbstractProtocol {
     }
 
     @Override
-    public <T> Invoker<T> refer(Class<T> type, URL url) throws RpcException {
+    protected <T> Invoker<T> doRefer(Class<T> type, URL url) throws RpcException {
         return new MockInvoker<T>(url);
     }
 }

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

@@ -23,15 +23,14 @@ import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.common.utils.ReflectUtils;
 import org.apache.dubbo.common.utils.StringUtils;
 import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.InvokeMode;
 import org.apache.dubbo.rpc.RpcInvocation;
 
 import java.lang.reflect.Method;
-import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.Future;
 import java.util.concurrent.atomic.AtomicLong;
 
 /**
@@ -65,7 +64,6 @@ public class RpcUtils {
         return null;
     }
 
-    // TODO why not get return type when initialize Invocation?
     public static Type[] getReturnTypes(Invocation invocation) {
         try {
             if (invocation != null && invocation.getInvoker() != null
@@ -80,24 +78,7 @@ public class RpcUtils {
                     if (method.getReturnType() == void.class) {
                         return null;
                     }
-                    Class<?> returnType = method.getReturnType();
-                    Type genericReturnType = method.getGenericReturnType();
-                    if (Future.class.isAssignableFrom(returnType)) {
-                        if (genericReturnType instanceof ParameterizedType) {
-                            Type actualArgType = ((ParameterizedType) genericReturnType).getActualTypeArguments()[0];
-                            if (actualArgType instanceof ParameterizedType) {
-                                returnType = (Class<?>) ((ParameterizedType) actualArgType).getRawType();
-                                genericReturnType = actualArgType;
-                            } else {
-                                returnType = (Class<?>) actualArgType;
-                                genericReturnType = returnType;
-                            }
-                        } else {
-                            returnType = null;
-                            genericReturnType = null;
-                        }
-                    }
-                    return new Type[]{returnType, genericReturnType};
+                    return ReflectUtils.getReturnTypes(method);
                 }
             }
         } catch (Throwable t) {
@@ -184,11 +165,22 @@ public class RpcUtils {
     }
 
     public static boolean isReturnTypeFuture(Invocation inv) {
-        return Boolean.TRUE.toString().equals(inv.getAttachment(Constants.FUTURE_RETURNTYPE_KEY));
+        Class<?> clazz = getReturnType(inv);
+        return (clazz != null && CompletableFuture.class.isAssignableFrom(clazz)) || isGenericAsync(inv);
     }
 
-    public static boolean hasFutureReturnType(Method method) {
-        return CompletableFuture.class.isAssignableFrom(method.getReturnType());
+    public static InvokeMode getInvokeMode(URL url, Invocation inv) {
+        if (isReturnTypeFuture(inv)) {
+            return InvokeMode.FUTURE;
+        } else if (isAsync(url, inv)) {
+            return InvokeMode.ASYNC;
+        } else {
+            return InvokeMode.SYNC;
+        }
+    }
+
+    public static boolean isGenericAsync(Invocation inv) {
+        return Constants.$INVOKE_ASYNC.equals(inv.getMethodName());
     }
 
     public static boolean isOneway(URL url, Invocation inv) {

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/RpcResultTest.java

@@ -26,7 +26,7 @@ public class RpcResultTest {
     @Test
     public void testRecreateWithNormalException() {
         NullPointerException npe = new NullPointerException();
-        RpcResult rpcResult = new RpcResult(npe);
+        AppResponse rpcResult = new AppResponse(npe);
         try {
             rpcResult.recreate();
             fail();
@@ -64,7 +64,7 @@ public class RpcResultTest {
         }
         // end construct a NullPointerException with empty stackTrace
 
-        RpcResult rpcResult = new RpcResult(throwable);
+        AppResponse rpcResult = new AppResponse(throwable);
         try {
             rpcResult.recreate();
             fail();

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/filter/ActiveLimitFilterTest.java

@@ -17,9 +17,9 @@
 package org.apache.dubbo.rpc.filter;
 
 import org.apache.dubbo.common.URL;
-import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcStatus;
 import org.apache.dubbo.rpc.support.BlockMyInvoker;
@@ -35,13 +35,14 @@ import java.util.concurrent.atomic.AtomicInteger;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotSame;
+import static org.junit.jupiter.api.Assertions.fail;
 
 /**
  * ActiveLimitFilterTest.java
  */
 public class ActiveLimitFilterTest {
 
-    Filter activeLimitFilter = new ActiveLimitFilter();
+    ActiveLimitFilter activeLimitFilter = new ActiveLimitFilter();
 
     @Test
     public void testInvokeNoActives() {
@@ -97,7 +98,7 @@ public class ActiveLimitFilterTest {
     }
 
     @Test
-    public void testInvokeTimeOut() {
+    public void testInvokeTimeOut() throws Exception {
         int totalThread = 100;
         int maxActives = 10;
         long timeout = 1;
@@ -120,9 +121,14 @@ public class ActiveLimitFilterTest {
                             e.printStackTrace();
                         }
                         try {
-                            activeLimitFilter.invoke(invoker, invocation);
+                            Result asyncResult = activeLimitFilter.invoke(invoker, invocation);
+                            Result result = asyncResult.get();
+                            activeLimitFilter.listener().onResponse(result, invoker, invocation);
                         } catch (RpcException expected) {
                             count.incrementAndGet();
+//                            activeLimitFilter.listener().onError(expected, invoker, invocation);
+                        } catch (Exception e) {
+                            fail();
                         }
                     } finally {
                         latchBlocking.countDown();
@@ -142,7 +148,7 @@ public class ActiveLimitFilterTest {
     }
 
     @Test
-    public void testInvokeNotTimeOut() {
+    public void testInvokeNotTimeOut() throws Exception {
         int totalThread = 100;
         int maxActives = 10;
         long timeout = 1000;
@@ -163,9 +169,14 @@ public class ActiveLimitFilterTest {
                             e.printStackTrace();
                         }
                         try {
-                            activeLimitFilter.invoke(invoker, invocation);
+                            Result asyncResult = activeLimitFilter.invoke(invoker, invocation);
+                            Result result = asyncResult.get();
+                            activeLimitFilter.listener().onResponse(result, invoker, invocation);
                         } catch (RpcException expected) {
                             count.incrementAndGet();
+                            activeLimitFilter.listener().onError(expected, invoker, invocation);
+                        } catch (Exception e) {
+                            fail();
                         }
                     } finally {
                         latchBlocking.countDown();
@@ -208,6 +219,7 @@ public class ActiveLimitFilterTest {
         try {
             activeLimitFilter.invoke(invoker, invocation);
         } catch (RuntimeException ex) {
+            activeLimitFilter.listener().onError(ex, invoker, invocation);
             int afterExceptionActiveCount = count.getActive();
             assertEquals(beforeExceptionActiveCount, afterExceptionActiveCount, "After exception active count should be same");
         }

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/filter/CompatibleFilterFilterTest.java

@@ -17,13 +17,14 @@
 package org.apache.dubbo.rpc.filter;
 
 import org.apache.dubbo.common.URL;
-import org.apache.dubbo.rpc.Filter;
+import org.apache.dubbo.rpc.AppResponse;
+import org.apache.dubbo.rpc.AsyncRpcResult;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.support.DemoService;
 import org.apache.dubbo.rpc.support.Type;
+
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
@@ -37,7 +38,7 @@ import static org.mockito.Mockito.mock;
  * CompatibleFilterTest.java
  */
 public class CompatibleFilterFilterTest {
-    private Filter compatibleFilter = new CompatibleFilter();
+    private CompatibleFilter compatibleFilter = new CompatibleFilter();
     private Invocation invocation;
     private Invoker invoker;
 
@@ -56,7 +57,7 @@ public class CompatibleFilterFilterTest {
         invoker = mock(Invoker.class);
         given(invoker.isAvailable()).willReturn(true);
         given(invoker.getInterface()).willReturn(DemoService.class);
-        RpcResult result = new RpcResult();
+        AppResponse result = new AppResponse();
         result.setValue("High");
         given(invoker.invoke(invocation)).willReturn(result);
         URL url = URL.valueOf("test://test:11/test?group=dubbo&version=1.1");
@@ -76,7 +77,7 @@ public class CompatibleFilterFilterTest {
         invoker = mock(Invoker.class);
         given(invoker.isAvailable()).willReturn(true);
         given(invoker.getInterface()).willReturn(DemoService.class);
-        RpcResult result = new RpcResult();
+        AppResponse result = new AppResponse();
         result.setException(new RuntimeException());
         result.setValue("High");
         given(invoker.invoke(invocation)).willReturn(result);
@@ -88,7 +89,7 @@ public class CompatibleFilterFilterTest {
     }
 
     @Test
-    public void testInvokerJsonPojoSerialization() {
+    public void testInvokerJsonPojoSerialization() throws Exception {
         invocation = mock(Invocation.class);
         given(invocation.getMethodName()).willReturn("enumlength");
         given(invocation.getParameterTypes()).willReturn(new Class<?>[]{Type[].class});
@@ -97,18 +98,20 @@ public class CompatibleFilterFilterTest {
         invoker = mock(Invoker.class);
         given(invoker.isAvailable()).willReturn(true);
         given(invoker.getInterface()).willReturn(DemoService.class);
-        RpcResult result = new RpcResult();
+        AppResponse result = new AppResponse();
         result.setValue("High");
-        given(invoker.invoke(invocation)).willReturn(result);
+        given(invoker.invoke(invocation)).willReturn(AsyncRpcResult.newDefaultAsyncResult(result, invocation));
         URL url = URL.valueOf("test://test:11/test?group=dubbo&version=1.1&serialization=json");
         given(invoker.getUrl()).willReturn(url);
 
-        Result filterResult = compatibleFilter.invoke(invoker, invocation);
-        assertEquals(Type.High, filterResult.getValue());
+        Result asyncResult = compatibleFilter.invoke(invoker, invocation);
+        Result rpcResult = asyncResult.get();
+        compatibleFilter.listener().onResponse(rpcResult, invoker, invocation);
+        assertEquals(Type.High, rpcResult.getValue());
     }
 
     @Test
-    public void testInvokerNonJsonEnumSerialization() {
+    public void testInvokerNonJsonEnumSerialization() throws Exception {
         invocation = mock(Invocation.class);
         given(invocation.getMethodName()).willReturn("enumlength");
         given(invocation.getParameterTypes()).willReturn(new Class<?>[]{Type[].class});
@@ -117,14 +120,16 @@ public class CompatibleFilterFilterTest {
         invoker = mock(Invoker.class);
         given(invoker.isAvailable()).willReturn(true);
         given(invoker.getInterface()).willReturn(DemoService.class);
-        RpcResult result = new RpcResult();
+        AppResponse result = new AppResponse();
         result.setValue("High");
-        given(invoker.invoke(invocation)).willReturn(result);
+        given(invoker.invoke(invocation)).willReturn(AsyncRpcResult.newDefaultAsyncResult(result, invocation));
         URL url = URL.valueOf("test://test:11/test?group=dubbo&version=1.1");
         given(invoker.getUrl()).willReturn(url);
 
-        Result filterResult = compatibleFilter.invoke(invoker, invocation);
-        assertEquals(Type.High, filterResult.getValue());
+        Result asyncResult = compatibleFilter.invoke(invoker, invocation);
+        Result rpcResult = asyncResult.get();
+        compatibleFilter.listener().onResponse(rpcResult, invoker, invocation);
+        assertEquals(Type.High, rpcResult.getValue());
     }
 
     @Test
@@ -137,7 +142,7 @@ public class CompatibleFilterFilterTest {
         invoker = mock(Invoker.class);
         given(invoker.isAvailable()).willReturn(true);
         given(invoker.getInterface()).willReturn(DemoService.class);
-        RpcResult result = new RpcResult();
+        AppResponse result = new AppResponse();
         result.setValue(new String[]{"High"});
         given(invoker.invoke(invocation)).willReturn(result);
         URL url = URL.valueOf("test://test:11/test?group=dubbo&version=1.1");
@@ -157,7 +162,7 @@ public class CompatibleFilterFilterTest {
         invoker = mock(Invoker.class);
         given(invoker.isAvailable()).willReturn(true);
         given(invoker.getInterface()).willReturn(DemoService.class);
-        RpcResult result = new RpcResult();
+        AppResponse result = new AppResponse();
         result.setValue("hello");
         given(invoker.invoke(invocation)).willReturn(result);
         URL url = URL.valueOf("test://test:11/test?group=dubbo&version=1.1");

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/filter/ConsumerContextFilterTest.java

@@ -21,6 +21,7 @@ import org.apache.dubbo.common.utils.NetUtils;
 import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.support.DemoService;
 import org.apache.dubbo.rpc.support.MockInvocation;
@@ -41,11 +42,13 @@ public class ConsumerContextFilterTest {
         URL url = URL.valueOf("test://test:11/test?group=dubbo&version=1.1");
         Invoker<DemoService> invoker = new MyInvoker<DemoService>(url);
         Invocation invocation = new MockInvocation();
-        consumerContextFilter.invoke(invoker, invocation);
-        assertEquals(invoker, RpcContext.getContext().getInvoker());
-        assertEquals(invocation, RpcContext.getContext().getInvocation());
-        assertEquals(NetUtils.getLocalHost() + ":0", RpcContext.getContext().getLocalAddressString());
-        assertEquals("test:11", RpcContext.getContext().getRemoteAddressString());
-
+        Result asyncResult = consumerContextFilter.invoke(invoker, invocation);
+        asyncResult.thenApplyWithContext(result -> {
+            assertEquals(invoker, RpcContext.getContext().getInvoker());
+            assertEquals(invocation, RpcContext.getContext().getInvocation());
+            assertEquals(NetUtils.getLocalHost() + ":0", RpcContext.getContext().getLocalAddressString());
+            assertEquals("test:11", RpcContext.getContext().getRemoteAddressString());
+            return result;
+        });
     }
 }

dubbo-rpc/dubbo-rpc-api/src/test/java/org/apache/dubbo/rpc/filter/ContextFilterTest.java

@@ -17,12 +17,12 @@
 package org.apache.dubbo.rpc.filter;
 
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.rpc.AppResponse;
 import org.apache.dubbo.rpc.Filter;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
-import org.apache.dubbo.rpc.RpcResult;
 import org.apache.dubbo.rpc.support.DemoService;
 import org.apache.dubbo.rpc.support.MockInvocation;
 import org.apache.dubbo.rpc.support.MyInvoker;
@@ -55,7 +55,7 @@ public class ContextFilterTest {
         invoker = mock(Invoker.class);
         given(invoker.isAvailable()).willReturn(true);
         given(invoker.getInterface()).willReturn(DemoService.class);
-        RpcResult result = new RpcResult();
+        AppResponse result = new AppResponse();
         result.setValue("High");
         given(invoker.invoke(invocation)).willReturn(result);
         URL url = URL.valueOf("test://test:11/test?group=dubbo&version=1.1");