[FLINK-4361] Introduce Flink's own future abstraction #2472
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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
| public FlinkCompletableFuture() { | ||
| promise = new scala.concurrent.impl.Promise.DefaultPromise<>(); | ||
| scalaFuture = promise.future(); | ||
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Good point, will remove it.
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Thanks for your review @KurtYoung. Will address your comments. |
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Thanks for the PR @tillrohrmann. You nicely abstracted away our Scala future/promise dependency. That lets us easily replace the Scala implementation with the Java 8 futures in the future (ha!).
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| * @return true if the future is completed; otherwise false | ||
| */ | ||
| boolean isDone(); |
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Why is this not named isCompleted()? That would be analogue to the complete() function.
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That's because I sticked to Java 8's CompletableFuture implementation where it is named the same.
I'm not super happy with the naming either. But I also see the benefit of sticking to Java 8's CompletableFuture interface. This will allow us to easily replace it once we switch to Java 8.
I think we have to decide whether we want to stick to Java 8's CompletableFuture or not. In the latter case we can rename other methods as well.
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I see. After all, it's a minor naming issue.
| <R> Future<R> exceptionallyAsync(ApplyFunction<Throwable, ? extends R> exceptionallyFunction, Executor executor); | ||
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| /** | ||
| * Applies the given function to the value of the future. The apply function can return a future |
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can return a future
should be
must return a future
or
returns a future
?
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You're right. The "can" should be removed. Will change it.
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The naming is not super nice, I agree. But there is a clear benefit for Java 8 familiar people to stick with something established. +1 for this from my side. Next time we get involved in the Java community processes, to make sure they have better names ;-) |
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Thanks for the review @KurtYoung, @mxm and @StephanEwen. I will merge this PR to the flip-6 branch. |
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.
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 apache#2472.
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 apache#2472.
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.
At the moment, the current future implementation is backed by Scala's futures.
The current set of operations comprises:
or the exceptional result
Additionally, Flink offers a CompletableFuture which can be completed with a regular
value or an exception: