| /* |
| * 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 static com.google.common.base.Preconditions.checkNotNull; |
| import static com.google.common.base.Preconditions.checkState; |
| |
| import com.google.common.annotations.GwtCompatible; |
| import com.google.common.collect.ImmutableCollection; |
| import com.google.j2objc.annotations.WeakOuter; |
| import java.util.concurrent.Callable; |
| import java.util.concurrent.CancellationException; |
| import java.util.concurrent.ExecutionException; |
| import java.util.concurrent.Executor; |
| import java.util.concurrent.RejectedExecutionException; |
| import org.checkerframework.checker.nullness.compatqual.NullableDecl; |
| |
| /** Aggregate future that computes its value by calling a callable. */ |
| @GwtCompatible |
| final class CombinedFuture<V> extends AggregateFuture<Object, V> { |
| CombinedFuture( |
| ImmutableCollection<? extends ListenableFuture<?>> futures, |
| boolean allMustSucceed, |
| Executor listenerExecutor, |
| AsyncCallable<V> callable) { |
| init( |
| new CombinedFutureRunningState( |
| futures, |
| allMustSucceed, |
| new AsyncCallableInterruptibleTask(callable, listenerExecutor))); |
| } |
| |
| CombinedFuture( |
| ImmutableCollection<? extends ListenableFuture<?>> futures, |
| boolean allMustSucceed, |
| Executor listenerExecutor, |
| Callable<V> callable) { |
| init( |
| new CombinedFutureRunningState( |
| futures, allMustSucceed, new CallableInterruptibleTask(callable, listenerExecutor))); |
| } |
| |
| private final class CombinedFutureRunningState extends RunningState { |
| private CombinedFutureInterruptibleTask task; |
| |
| CombinedFutureRunningState( |
| ImmutableCollection<? extends ListenableFuture<?>> futures, |
| boolean allMustSucceed, |
| CombinedFutureInterruptibleTask task) { |
| super(futures, allMustSucceed, false); |
| this.task = task; |
| } |
| |
| @Override |
| void collectOneValue(boolean allMustSucceed, int index, @NullableDecl Object returnValue) {} |
| |
| @Override |
| void handleAllCompleted() { |
| CombinedFutureInterruptibleTask localTask = task; |
| if (localTask != null) { |
| localTask.execute(); |
| } else { |
| checkState(isDone()); |
| } |
| } |
| |
| @Override |
| void releaseResourcesAfterFailure() { |
| super.releaseResourcesAfterFailure(); |
| this.task = null; |
| } |
| |
| @Override |
| void interruptTask() { |
| CombinedFutureInterruptibleTask localTask = task; |
| if (localTask != null) { |
| localTask.interruptTask(); |
| } |
| } |
| } |
| |
| @WeakOuter |
| private abstract class CombinedFutureInterruptibleTask<T> extends InterruptibleTask<T> { |
| private final Executor listenerExecutor; |
| boolean thrownByExecute = true; |
| |
| public CombinedFutureInterruptibleTask(Executor listenerExecutor) { |
| this.listenerExecutor = checkNotNull(listenerExecutor); |
| } |
| |
| @Override |
| final boolean isDone() { |
| return CombinedFuture.this.isDone(); |
| } |
| |
| final void execute() { |
| try { |
| listenerExecutor.execute(this); |
| } catch (RejectedExecutionException e) { |
| if (thrownByExecute) { |
| setException(e); |
| } |
| } |
| } |
| |
| @Override |
| final void afterRanInterruptibly(T result, Throwable error) { |
| if (error != null) { |
| if (error instanceof ExecutionException) { |
| setException(error.getCause()); |
| } else if (error instanceof CancellationException) { |
| cancel(false); |
| } else { |
| setException(error); |
| } |
| } else { |
| setValue(result); |
| } |
| } |
| |
| abstract void setValue(T value); |
| } |
| |
| @WeakOuter |
| private final class AsyncCallableInterruptibleTask |
| extends CombinedFutureInterruptibleTask<ListenableFuture<V>> { |
| private final AsyncCallable<V> callable; |
| |
| public AsyncCallableInterruptibleTask(AsyncCallable<V> callable, Executor listenerExecutor) { |
| super(listenerExecutor); |
| this.callable = checkNotNull(callable); |
| } |
| |
| @Override |
| ListenableFuture<V> runInterruptibly() throws Exception { |
| thrownByExecute = false; |
| ListenableFuture<V> result = callable.call(); |
| return checkNotNull( |
| result, |
| "AsyncCallable.call returned null instead of a Future. " |
| + "Did you mean to return immediateFuture(null)? %s", |
| callable); |
| } |
| |
| @Override |
| void setValue(ListenableFuture<V> value) { |
| setFuture(value); |
| } |
| |
| @Override |
| String toPendingString() { |
| return callable.toString(); |
| } |
| } |
| |
| @WeakOuter |
| private final class CallableInterruptibleTask extends CombinedFutureInterruptibleTask<V> { |
| private final Callable<V> callable; |
| |
| public CallableInterruptibleTask(Callable<V> callable, Executor listenerExecutor) { |
| super(listenerExecutor); |
| this.callable = checkNotNull(callable); |
| } |
| |
| @Override |
| V runInterruptibly() throws Exception { |
| thrownByExecute = false; |
| return callable.call(); |
| } |
| |
| @Override |
| void setValue(V value) { |
| CombinedFuture.this.set(value); |
| } |
| |
| @Override |
| String toPendingString() { |
| return callable.toString(); |
| } |
| } |
| } |