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Posted to commits@flink.apache.org by tr...@apache.org on 2016/09/21 08:09:53 UTC
flink git commit: [FLINK-4361] Introduce Flink's own future
abstraction
Repository: flink
Updated Branches:
refs/heads/flip-6 d159de62f -> 11cc6b95b
[FLINK-4361] Introduce Flink's own future abstraction
Flink's future abstraction whose API is similar to Java 8's CompletableFuture.
That's in order to ease a future transition to this class once we ditch Java 7.
The current set of operations comprises:
- isDone to check the completion of the future
- get/getNow to obtain the future's value
- cancel to cancel the future (best effort basis)
- thenApplyAsync to transform the future's value into another value
- thenAcceptAsync to register a callback for a successful completion of the future
- exceptionallyAsync to register a callback for an exception completion of the future
- thenComposeAsync to transform the future's value and flatten the returned future
- handleAsync to register a callback which is called either with the regular result
or the exceptional result
Additionally, Flink offers a CompletableFuture which can be completed with a regular
value or an exception:
- complete/completeExceptionally
Complete FlinkCompletableFuture exceptionally with a CanellationException upon cancel
This closes #2472.
Project: http://git-wip-us.apache.org/repos/asf/flink/repo
Commit: http://git-wip-us.apache.org/repos/asf/flink/commit/11cc6b95
Tree: http://git-wip-us.apache.org/repos/asf/flink/tree/11cc6b95
Diff: http://git-wip-us.apache.org/repos/asf/flink/diff/11cc6b95
Branch: refs/heads/flip-6
Commit: 11cc6b95bab5c3d17dd1182f3ad87df4184aaa4a
Parents: d159de6
Author: Till Rohrmann <tr...@apache.org>
Authored: Fri Sep 2 21:13:34 2016 +0200
Committer: Till Rohrmann <tr...@apache.org>
Committed: Wed Sep 21 10:09:07 2016 +0200
----------------------------------------------------------------------
.../runtime/concurrent/AcceptFunction.java | 34 +++
.../flink/runtime/concurrent/ApplyFunction.java | 36 +++
.../flink/runtime/concurrent/BiFunction.java | 38 +++
.../runtime/concurrent/CompletableFuture.java | 47 ++++
.../apache/flink/runtime/concurrent/Future.java | 156 +++++++++++
.../concurrent/impl/FlinkCompletableFuture.java | 71 +++++
.../runtime/concurrent/impl/FlinkFuture.java | 273 +++++++++++++++++++
.../runtime/concurrent/FlinkFutureTest.java | 269 ++++++++++++++++++
8 files changed, 924 insertions(+)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/flink/blob/11cc6b95/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/AcceptFunction.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/AcceptFunction.java b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/AcceptFunction.java
new file mode 100644
index 0000000..a300647
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/AcceptFunction.java
@@ -0,0 +1,34 @@
+/*
+ * 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.flink.runtime.concurrent;
+
+/**
+ * Function which is called with a single argument and does not return a value.
+ *
+ * @param <T> type of the argument
+ */
+public interface AcceptFunction<T> {
+
+ /**
+ * Method which handles the function call.
+ *
+ * @param value is the function's argument
+ */
+ void accept(T value);
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/11cc6b95/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/ApplyFunction.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/ApplyFunction.java b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/ApplyFunction.java
new file mode 100644
index 0000000..64def98
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/ApplyFunction.java
@@ -0,0 +1,36 @@
+/*
+ * 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.flink.runtime.concurrent;
+
+/**
+ * Function which is called with a single argument.
+ *
+ * @param <V> type of the argument
+ * @param <R> type of the return value
+ */
+public interface ApplyFunction<V, R> {
+
+ /**
+ * Method which handles the function call.
+ *
+ * @param value is the single argument
+ * @return the function value
+ */
+ R apply(V value);
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/11cc6b95/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/BiFunction.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/BiFunction.java b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/BiFunction.java
new file mode 100644
index 0000000..2b09de8
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/BiFunction.java
@@ -0,0 +1,38 @@
+/*
+ * 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.flink.runtime.concurrent;
+
+/**
+ * Function which is called with two arguments and returns a value.
+ *
+ * @param <T> type of the first argument
+ * @param <U> type of the second argument
+ * @param <R> type of the return value
+ */
+public interface BiFunction<T, U, R> {
+
+ /**
+ * Method which handles the function call.
+ *
+ * @param t first argument
+ * @param u second argument
+ * @return the function value
+ */
+ R apply(T t, U u);
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/11cc6b95/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/CompletableFuture.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/CompletableFuture.java b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/CompletableFuture.java
new file mode 100644
index 0000000..5288bf2
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/CompletableFuture.java
@@ -0,0 +1,47 @@
+/*
+ * 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.flink.runtime.concurrent;
+
+/**
+ * Flink's completable future abstraction. A completable future can be completed with a regular
+ * value or an exception.
+ *
+ * @param <T> type of the future's value
+ */
+public interface CompletableFuture<T> extends Future<T> {
+
+ /**
+ * Completes the future with the given value. The complete operation only succeeds if the future
+ * has not been completed before. Whether it is successful or not is returned by the method.
+ *
+ * @param value to complete the future with
+ * @return true if the completion was successful; otherwise false
+ */
+ boolean complete(T value);
+
+ /**
+ * Completes the future with the given exception. The complete operation only succeeds if the
+ * future has not been completed before. Whether it is successful or not is returned by the
+ * method.
+ *
+ * @param t the exception to complete the future with
+ * @return true if the completion was successful; otherwise false
+ */
+ boolean completeExceptionally(Throwable t);
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/11cc6b95/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/Future.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/Future.java b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/Future.java
new file mode 100644
index 0000000..b32bcd4
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/Future.java
@@ -0,0 +1,156 @@
+/*
+ * 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.flink.runtime.concurrent;
+
+import java.util.concurrent.CancellationException;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executor;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+/**
+ * Flink's basic future abstraction. A future represents an asynchronous operation whose result
+ * will be contained in this instance upon completion.
+ *
+ * @param <T> type of the future's result
+ */
+public interface Future<T> {
+
+ /**
+ * Checks if the future has been completed. A future is completed, if the result has been
+ * delivered.
+ *
+ * @return true if the future is completed; otherwise false
+ */
+ boolean isDone();
+
+ /**
+ * Tries to cancel the future's operation. Note that not all future operations can be canceled.
+ * The result of the cancelling will be returned.
+ *
+ * @param mayInterruptIfRunning true iff the future operation may be interrupted
+ * @return true if the cancelling was successful; otherwise false
+ */
+ boolean cancel(boolean mayInterruptIfRunning);
+
+ /**
+ * Gets the result value of the future. If the future has not been completed, then this
+ * operation will block indefinitely until the result has been delivered.
+ *
+ * @return the result value
+ * @throws CancellationException if the future has been cancelled
+ * @throws InterruptedException if the current thread was interrupted while waiting for the result
+ * @throws ExecutionException if the future has been completed with an exception
+ */
+ T get() throws InterruptedException, ExecutionException;
+
+ /**
+ * Gets the result value of the future. If the future has not been done, then this operation
+ * will block the given timeout value. If the result has not been delivered within the timeout,
+ * then the method throws an {@link TimeoutException}.
+ *
+ * @param timeout the time to wait for the future to be done
+ * @param unit time unit for the timeout argument
+ * @return the result value
+ * @throws CancellationException if the future has been cancelled
+ * @throws InterruptedException if the current thread was interrupted while waiting for the result
+ * @throws ExecutionException if the future has been completed with an exception
+ * @throws TimeoutException if the future has not been completed within the given timeout
+ */
+ T get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException;
+
+ /**
+ * Gets the value of the future. If the future has not been completed when calling this
+ * function, the given value is returned.
+ *
+ * @param valueIfAbsent value which is returned if the future has not been completed
+ * @return value of the future or the given value if the future has not been completed
+ * @throws ExecutionException if the future has been completed with an exception
+ */
+ T getNow(T valueIfAbsent) throws ExecutionException;
+
+ /**
+ * Applies the given function to the value of the future. The result of the apply function is
+ * the value of the newly returned future.
+ * <p>
+ * The apply function is executed asynchronously by the given executor.
+ *
+ * @param applyFunction function to apply to the future's value
+ * @param executor used to execute the given apply function asynchronously
+ * @param <R> type of the apply function's return value
+ * @return future representing the return value of the given apply function
+ */
+ <R> Future<R> thenApplyAsync(ApplyFunction<? super T, ? extends R> applyFunction, Executor executor);
+
+ /**
+ * Applies the accept function to the value of the future. Unlike the {@link ApplyFunction}, the
+ * {@link AcceptFunction} does not return a value. The returned future, thus, represents only
+ * the completion of the accept callback.
+ * <p>
+ * The accept function is executed asynchronously by the given executor.
+ *
+ * @param acceptFunction function to apply to the future's value
+ * @param executor used to execute the given apply function asynchronously
+ * @return future representing the completion of the accept callback
+ */
+ Future<Void> thenAcceptAsync(AcceptFunction<? super T> acceptFunction, Executor executor);
+
+ /**
+ * Applies the given function to the value of the future if the future has been completed
+ * exceptionally. The completing exception is given to the apply function which can return a new
+ * value which is the value of the returned future.
+ * <p>
+ * The apply function is executed asynchronously by the given executor.
+ *
+ * @param exceptionallyFunction to apply to the future's value if it is an exception
+ * @param executor used to execute the given apply function asynchronously
+ * @param <R> type of the apply function's return value
+ * @return future representing the return value of the given apply function
+ */
+ <R> Future<R> exceptionallyAsync(ApplyFunction<Throwable, ? extends R> exceptionallyFunction, Executor executor);
+
+ /**
+ * Applies the given function to the value of the future. The apply function returns a future
+ * result, which is flattened. This means that the resulting future of this method represents
+ * the future's value of the apply function.
+ * <p>
+ * The apply function is executed asynchronously by the given executor.
+ *
+ * @param composeFunction to apply to the future's value. The function returns a future which is
+ * flattened
+ * @param executor used to execute the given apply function asynchronously
+ * @param <R> type of the returned future's value
+ * @return future representing the flattened return value of the apply function
+ */
+ <R> Future<R> thenComposeAsync(ApplyFunction<? super T, Future<? extends R>> composeFunction, Executor executor);
+
+ /**
+ * Applies the given handle function to the result of the future. The result can either be the
+ * future's value or the exception with which the future has been completed. The two cases are
+ * mutually exclusive. The result of the handle function is the returned future's value.
+ * <p>
+ * The handle function is executed asynchronously by the given executor.
+ *
+ * @param biFunction applied to the result (normal and exceptional) of the future
+ * @param executor used to execute the handle function asynchronously
+ * @param <R> type of the handle function's return value
+ * @return future representing the handle function's return value
+ */
+ <R> Future<R> handleAsync(BiFunction<? super T, Throwable, ? extends R> biFunction, Executor executor);
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/11cc6b95/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/impl/FlinkCompletableFuture.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/impl/FlinkCompletableFuture.java b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/impl/FlinkCompletableFuture.java
new file mode 100644
index 0000000..5566880
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/impl/FlinkCompletableFuture.java
@@ -0,0 +1,71 @@
+/*
+ * 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.flink.runtime.concurrent.impl;
+
+import org.apache.flink.runtime.concurrent.CompletableFuture;
+import org.apache.flink.util.Preconditions;
+import scala.concurrent.Promise;
+
+import java.util.concurrent.CancellationException;
+
+/**
+ * Implementation of {@link CompletableFuture} which is backed by {@link Promise}.
+ *
+ * @param <T> type of the future's value
+ */
+public class FlinkCompletableFuture<T> extends FlinkFuture<T> implements CompletableFuture<T> {
+
+ private final Promise<T> promise;
+
+ public FlinkCompletableFuture() {
+ promise = new scala.concurrent.impl.Promise.DefaultPromise<>();
+ scalaFuture = promise.future();
+ }
+
+ @Override
+ public boolean complete(T value) {
+ Preconditions.checkNotNull(value);
+
+ try {
+ promise.success(value);
+
+ return true;
+ } catch (IllegalStateException e) {
+ return false;
+ }
+ }
+
+ @Override
+ public boolean completeExceptionally(Throwable t) {
+ Preconditions.checkNotNull(t);
+
+ try {
+ promise.failure(t);
+
+ return true;
+ } catch (IllegalStateException e) {
+ return false;
+ }
+ }
+
+ @Override
+ public boolean cancel(boolean mayInterruptIfRunning) {
+ return completeExceptionally(new CancellationException("Future has been canceled."));
+ }
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/11cc6b95/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/impl/FlinkFuture.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/impl/FlinkFuture.java b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/impl/FlinkFuture.java
new file mode 100644
index 0000000..361cd3d
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/concurrent/impl/FlinkFuture.java
@@ -0,0 +1,273 @@
+/*
+ * 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.flink.runtime.concurrent.impl;
+
+import akka.dispatch.ExecutionContexts$;
+import akka.dispatch.Futures;
+import akka.dispatch.Mapper;
+import akka.dispatch.Recover;
+import org.apache.flink.runtime.concurrent.AcceptFunction;
+import org.apache.flink.runtime.concurrent.ApplyFunction;
+import org.apache.flink.runtime.concurrent.Future;
+import org.apache.flink.runtime.concurrent.BiFunction;
+import org.apache.flink.util.Preconditions;
+import scala.Option;
+import scala.concurrent.Await;
+import scala.concurrent.ExecutionContext;
+import scala.concurrent.duration.Duration;
+import scala.concurrent.duration.FiniteDuration;
+import scala.util.Failure;
+import scala.util.Success;
+import scala.util.Try;
+
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executor;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+/**
+ * Implementation of {@link Future} which is backed by {@link scala.concurrent.Future}.
+ *
+ * @param <T> type of the future's value
+ */
+public class FlinkFuture<T> implements Future<T> {
+
+ protected scala.concurrent.Future<T> scalaFuture;
+
+ FlinkFuture() {
+ scalaFuture = null;
+ }
+
+ public FlinkFuture(scala.concurrent.Future<T> scalaFuture) {
+ this.scalaFuture = Preconditions.checkNotNull(scalaFuture);
+ }
+
+ //-----------------------------------------------------------------------------------
+ // Future's methods
+ //-----------------------------------------------------------------------------------
+
+ @Override
+ public boolean isDone() {
+ return scalaFuture.isCompleted();
+ }
+
+ @Override
+ public boolean cancel(boolean mayInterruptIfRunning) {
+ return false;
+ }
+
+ @Override
+ public T get() throws InterruptedException, ExecutionException {
+ Preconditions.checkNotNull(scalaFuture);
+
+ try {
+ return Await.result(scalaFuture, Duration.Inf());
+ } catch (InterruptedException e) {
+ throw e;
+ } catch (Exception e) {
+ throw new ExecutionException(e);
+ }
+ }
+
+ @Override
+ public T get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException {
+ Preconditions.checkNotNull(scalaFuture);
+ Preconditions.checkArgument(timeout >= 0L, "The timeout value has to be larger or " +
+ "equal than 0.");
+
+ try {
+ return Await.result(scalaFuture, new FiniteDuration(timeout, unit));
+ } catch (InterruptedException | TimeoutException e) {
+ throw e;
+ } catch (Exception e) {
+ throw new ExecutionException(e);
+ }
+ }
+
+ @Override
+ public T getNow(T valueIfAbsent) throws ExecutionException {
+ Preconditions.checkNotNull(scalaFuture);
+ Preconditions.checkNotNull(valueIfAbsent);
+
+ Option<Try<T>> value = scalaFuture.value();
+
+ if (value.isDefined()) {
+ Try<T> tri = value.get();
+
+ if (tri instanceof Success) {
+ return ((Success<T>)tri).value();
+ } else {
+ throw new ExecutionException(((Failure<T>)tri).exception());
+ }
+ } else {
+ return valueIfAbsent;
+ }
+ }
+
+ @Override
+ public <R> Future<R> thenApplyAsync(final ApplyFunction<? super T, ? extends R> applyFunction, Executor executor) {
+ Preconditions.checkNotNull(scalaFuture);
+ Preconditions.checkNotNull(applyFunction);
+ Preconditions.checkNotNull(executor);
+
+ scala.concurrent.Future<R> mappedFuture = scalaFuture.map(new Mapper<T, R>() {
+ @Override
+ public R apply(T value) {
+ return applyFunction.apply(value);
+ }
+ }, createExecutionContext(executor));
+
+ return new FlinkFuture<>(mappedFuture);
+ }
+
+ @Override
+ public Future<Void> thenAcceptAsync(final AcceptFunction<? super T> acceptFunction, Executor executor) {
+ Preconditions.checkNotNull(scalaFuture);
+ Preconditions.checkNotNull(acceptFunction);
+ Preconditions.checkNotNull(executor);
+
+ scala.concurrent.Future<Void> acceptedFuture = scalaFuture.map(new Mapper<T, Void>() {
+ @Override
+ public Void apply(T value) {
+ acceptFunction.accept(value);
+
+ return null;
+ }
+ }, createExecutionContext(executor));
+
+ return new FlinkFuture<>(acceptedFuture);
+ }
+
+ @Override
+ public <R> Future<R> exceptionallyAsync(final ApplyFunction<Throwable, ? extends R> exceptionallyFunction, Executor executor) {
+ Preconditions.checkNotNull(scalaFuture);
+ Preconditions.checkNotNull(exceptionallyFunction);
+ Preconditions.checkNotNull(executor);
+
+ scala.concurrent.Future<R> recoveredFuture = scalaFuture.recover(new Recover<R>() {
+ @Override
+ public R recover(Throwable failure) throws Throwable {
+ return exceptionallyFunction.apply(failure);
+ }
+ }, createExecutionContext(executor));
+
+ return new FlinkFuture<>(recoveredFuture);
+ }
+
+ @Override
+ public <R> Future<R> thenComposeAsync(final ApplyFunction<? super T, Future<? extends R>> applyFunction, final Executor executor) {
+ Preconditions.checkNotNull(scalaFuture);
+ Preconditions.checkNotNull(applyFunction);
+ Preconditions.checkNotNull(executor);
+
+ scala.concurrent.Future<R> flatMappedFuture = scalaFuture.flatMap(new Mapper<T, scala.concurrent.Future<R>>() {
+ @Override
+ public scala.concurrent.Future<R> apply(T value) {
+ final Future<? extends R> future = applyFunction.apply(value);
+
+ if (future instanceof FlinkFuture) {
+ @SuppressWarnings("unchecked")
+ FlinkFuture<R> flinkFuture = (FlinkFuture<R>) future;
+
+ return flinkFuture.scalaFuture;
+ } else {
+ return Futures.future(new Callable<R>() {
+ @Override
+ public R call() throws Exception {
+ return future.get();
+ }
+ }, createExecutionContext(executor));
+ }
+ }
+ }, createExecutionContext(executor));
+
+ return new FlinkFuture<>(flatMappedFuture);
+ }
+
+ @Override
+ public <R> Future<R> handleAsync(final BiFunction<? super T, Throwable, ? extends R> biFunction, Executor executor) {
+ Preconditions.checkNotNull(scalaFuture);
+ Preconditions.checkNotNull(biFunction);
+ Preconditions.checkNotNull(executor);
+
+ scala.concurrent.Future<R> mappedFuture = scalaFuture.map(new Mapper<T, R>() {
+ @Override
+ public R checkedApply(T value) throws Exception {
+ try {
+ return biFunction.apply(value, null);
+ } catch (Throwable t) {
+ throw new FlinkFuture.WrapperException(t);
+ }
+ }
+ }, createExecutionContext(executor));
+
+ scala.concurrent.Future<R> recoveredFuture = mappedFuture.recover(new Recover<R>() {
+ @Override
+ public R recover(Throwable failure) throws Throwable {
+ if (failure instanceof FlinkFuture.WrapperException) {
+ throw failure.getCause();
+ } else {
+ return biFunction.apply(null, failure);
+ }
+ }
+ }, createExecutionContext(executor));
+
+
+ return new FlinkFuture<>(recoveredFuture);
+ }
+
+ //-----------------------------------------------------------------------------------
+ // Static factory methods
+ //-----------------------------------------------------------------------------------
+
+ /**
+ * Creates a future whose value is determined by the asynchronously executed callable.
+ *
+ * @param callable whose value is delivered by the future
+ * @param executor to be used to execute the callable
+ * @param <T> type of the future's value
+ * @return future which represents the value of the callable
+ */
+ public static <T> Future<T> supplyAsync(Callable<T> callable, Executor executor) {
+ Preconditions.checkNotNull(callable);
+ Preconditions.checkNotNull(executor);
+
+ scala.concurrent.Future<T> scalaFuture = Futures.future(callable, createExecutionContext(executor));
+
+ return new FlinkFuture<>(scalaFuture);
+ }
+
+ //-----------------------------------------------------------------------------------
+ // Helper functions and types
+ //-----------------------------------------------------------------------------------
+
+ private static ExecutionContext createExecutionContext(Executor executor) {
+ return ExecutionContexts$.MODULE$.fromExecutor(executor);
+ }
+
+ private static class WrapperException extends Exception {
+
+ private static final long serialVersionUID = 6533166370660884091L;
+
+ WrapperException(Throwable cause) {
+ super(cause);
+ }
+ }
+}
http://git-wip-us.apache.org/repos/asf/flink/blob/11cc6b95/flink-runtime/src/test/java/org/apache/flink/runtime/concurrent/FlinkFutureTest.java
----------------------------------------------------------------------
diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/concurrent/FlinkFutureTest.java b/flink-runtime/src/test/java/org/apache/flink/runtime/concurrent/FlinkFutureTest.java
new file mode 100644
index 0000000..bd5af66
--- /dev/null
+++ b/flink-runtime/src/test/java/org/apache/flink/runtime/concurrent/FlinkFutureTest.java
@@ -0,0 +1,269 @@
+/*
+ * 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.flink.runtime.concurrent;
+
+import org.apache.flink.runtime.concurrent.impl.FlinkCompletableFuture;
+import org.apache.flink.runtime.concurrent.impl.FlinkFuture;
+import org.apache.flink.util.TestLogger;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+/**
+ * Tests for Flink's future implementation.
+ */
+public class FlinkFutureTest extends TestLogger {
+
+ private static ExecutorService executor;
+
+ @BeforeClass
+ public static void setup() {
+ executor = Executors.newSingleThreadExecutor();
+ }
+
+ @AfterClass
+ public static void teardown() {
+ executor.shutdown();
+ }
+
+ @Test
+ public void testFutureApply() throws Exception {
+ int expectedValue = 42;
+
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+
+ Future<String> appliedFuture = initialFuture.thenApplyAsync(new ApplyFunction<Integer, String>() {
+ @Override
+ public String apply(Integer value) {
+ return String.valueOf(value);
+ }
+ }, executor);
+
+ initialFuture.complete(expectedValue);
+
+ assertEquals(String.valueOf(expectedValue), appliedFuture.get());
+ }
+
+ @Test(expected = TimeoutException.class)
+ public void testFutureGetTimeout() throws InterruptedException, ExecutionException, TimeoutException {
+ CompletableFuture<Integer> future = new FlinkCompletableFuture<>();
+
+ future.get(10, TimeUnit.MILLISECONDS);
+
+ fail("Get should have thrown a timeout exception.");
+ }
+
+ @Test(expected = TestException.class)
+ public void testExceptionalCompletion() throws Throwable {
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+
+ initialFuture.completeExceptionally(new TestException("Test exception"));
+
+ try {
+ initialFuture.get();
+
+ fail("Get should have thrown an exception.");
+ } catch (ExecutionException e) {
+ throw e.getCause();
+ }
+ }
+
+ /**
+ * Tests that an exception is propagated through an apply function.
+ */
+ @Test(expected = TestException.class)
+ public void testExceptionPropagation() throws Throwable {
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+
+ Future<String> mappedFuture = initialFuture.thenApplyAsync(new ApplyFunction<Integer, String>() {
+ @Override
+ public String apply(Integer value) {
+ throw new TestException("Test exception");
+ }
+ }, executor);
+
+ Future<String> mapped2Future = mappedFuture.thenApplyAsync(new ApplyFunction<String, String>() {
+ @Override
+ public String apply(String value) {
+ return "foobar";
+ }
+ }, executor);
+
+ initialFuture.complete(42);
+
+ try {
+ mapped2Future.get();
+
+ fail("Get should have thrown an exception.");
+ } catch (ExecutionException e) {
+ throw e.getCause();
+ }
+ }
+
+ @Test
+ public void testExceptionally() throws ExecutionException, InterruptedException {
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+ String exceptionMessage = "Foobar";
+
+ Future<String> recovered = initialFuture.exceptionallyAsync(new ApplyFunction<Throwable, String>() {
+ @Override
+ public String apply(Throwable value) {
+ return value.getMessage();
+ }
+ }, executor);
+
+ initialFuture.completeExceptionally(new TestException(exceptionMessage));
+
+ String actualMessage = recovered.get();
+
+ assertEquals(exceptionMessage, actualMessage);
+ }
+
+ @Test
+ public void testCompose() throws ExecutionException, InterruptedException {
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+
+ final int expectedValue = 42;
+
+ Future<Integer> composedFuture = initialFuture.thenComposeAsync(new ApplyFunction<Integer, Future<? extends Integer>>() {
+ @Override
+ public Future<? extends Integer> apply(Integer value) {
+ return FlinkFuture.supplyAsync(new Callable<Integer>() {
+ @Override
+ public Integer call() throws Exception {
+ return expectedValue;
+ }
+ }, executor);
+ }
+ }, executor);
+
+ initialFuture.complete(42);
+
+ int actualValue = composedFuture.get();
+
+ assertEquals(expectedValue, actualValue);
+ }
+
+ @Test
+ public void testGetNow() throws ExecutionException {
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+
+ final int absentValue = 41;
+
+ assertEquals(new Integer(absentValue), initialFuture.getNow(absentValue));
+ }
+
+ @Test
+ public void testAccept() throws ExecutionException, InterruptedException {
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+ final AtomicInteger atomicInteger = new AtomicInteger(0);
+ int expectedValue = 42;
+
+ Future<Void> result = initialFuture.thenAcceptAsync(new AcceptFunction<Integer>() {
+ @Override
+ public void accept(Integer value) {
+ atomicInteger.set(value);
+ }
+ }, executor);
+
+ initialFuture.complete(expectedValue);
+
+ result.get();
+
+ assertEquals(expectedValue, atomicInteger.get());
+ }
+
+ @Test
+ public void testHandle() throws ExecutionException, InterruptedException {
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+ int expectedValue = 43;
+
+ Future<String> result = initialFuture.handleAsync(new BiFunction<Integer, Throwable, String>() {
+ @Override
+ public String apply(Integer integer, Throwable throwable) {
+ if (integer != null) {
+ return String.valueOf(integer);
+ } else {
+ return throwable.getMessage();
+ }
+ }
+ }, executor);
+
+ initialFuture.complete(expectedValue);
+
+ assertEquals(String.valueOf(expectedValue), result.get());
+ }
+
+ @Test
+ public void testHandleException() throws ExecutionException, InterruptedException {
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+ String exceptionMessage = "foobar";
+
+ Future<String> result = initialFuture.handleAsync(new BiFunction<Integer, Throwable, String>() {
+ @Override
+ public String apply(Integer integer, Throwable throwable) {
+ if (integer != null) {
+ return String.valueOf(integer);
+ } else {
+ return throwable.getMessage();
+ }
+ }
+ }, executor);
+
+ initialFuture.completeExceptionally(new TestException(exceptionMessage));
+
+ assertEquals(exceptionMessage, result.get());
+ }
+
+ @Test
+ public void testMultipleCompleteOperations() throws ExecutionException, InterruptedException {
+ CompletableFuture<Integer> initialFuture = new FlinkCompletableFuture<>();
+ int expectedValue = 42;
+
+ assertTrue(initialFuture.complete(expectedValue));
+
+ assertFalse(initialFuture.complete(1337));
+
+ assertFalse(initialFuture.completeExceptionally(new TestException("foobar")));
+
+ assertEquals(new Integer(expectedValue), initialFuture.get());
+ }
+
+ private static class TestException extends RuntimeException {
+
+ private static final long serialVersionUID = -1274022962838535130L;
+
+ public TestException(String message) {
+ super(message);
+ }
+ }
+}