AsyncFunction.kt
/*
* Copyright 2023 The Android Open Source Project
*
* 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 androidx.camera.impl.utils.futures
import com.google.common.util.concurrent.ListenableFuture
import java.util.concurrent.Future
/**
* Cloned from concurrent-futures package in Guava to AndroidX namespace since we would need
* ListenableFuture related implementation but not want to include whole Guava library.
*
* Transforms a value, possibly asynchronously. For an example usage and more information, see
* [Futures.transformAsync].
*
* @author Chris Povirk
* @since 11.0
* @param <I>
* @param <O>
</O></I> */
fun interface AsyncFunction<I, O> {
/**
* Returns an output `Future` to use in place of the given `input`. The output
* `Future` need not be [done][Future.isDone], making `AsyncFunction`
* suitable for asynchronous derivations.
*
*
* Throwing an exception from this method is equivalent to returning a failing `Future`.
*/
@Throws(Exception::class)
fun apply(input: I?): ListenableFuture<O>
}