FutureUtil.java
/*
* Copyright 2020 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.
*/
// @exportToFramework:skipFile()
package androidx.appsearch.localstorage.util;
import androidx.annotation.NonNull;
import androidx.annotation.RestrictTo;
import androidx.concurrent.futures.ResolvableFuture;
import androidx.core.util.Preconditions;
import com.google.common.util.concurrent.ListenableFuture;
import java.util.concurrent.Callable;
import java.util.concurrent.Executor;
/**
* Utilities for working with {@link com.google.common.util.concurrent.ListenableFuture}.
* @hide
*/
@RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
public final class FutureUtil {
private FutureUtil() {}
/** Executes the given lambda on the given executor and returns a {@link ListenableFuture}. */
@NonNull
public static <T> ListenableFuture<T> execute(
@NonNull Executor executor,
@NonNull Callable<T> callable) {
Preconditions.checkNotNull(executor);
Preconditions.checkNotNull(callable);
ResolvableFuture<T> future = ResolvableFuture.create();
executor.execute(() -> {
if (!future.isCancelled()) {
try {
future.set(callable.call());
} catch (Throwable t) {
future.setException(t);
}
}
});
return future;
}
}