/*
* Copyright (C) 2015 The Guava Authors
*
* Licensed 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 com.google.common.util.concurrent;
import com.google.common.annotations.Beta;
import com.google.common.annotations.GwtCompatible;
import java.util.concurrent.Future;
/**
* Computes a value, possibly asynchronously. For an example usage and more information, see {@link
* Futures.FutureCombiner#callAsync(AsyncCallable, java.util.concurrent.Executor)}.
*
* <p>Much like {@link java.util.concurrent.Callable}, but returning a {@link ListenableFuture}
* result.
*
* @since 20.0
*/
@Beta
@GwtCompatible
public interface AsyncCallable<V> {
/**
* Computes a result {@code Future}. The output {@code Future} need not be {@linkplain
* Future#isDone done}, making {@code AsyncCallable} suitable for asynchronous derivations.
*
* <p>Throwing an exception from this method is equivalent to returning a failing {@link
* ListenableFuture}.
*/
ListenableFuture<V> call() throws Exception;
}