001/*
002 * Copyright (C) 2011 The Guava Authors
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
005 * in compliance with the License. You may obtain a copy of the License at
006 *
007 * http://www.apache.org/licenses/LICENSE-2.0
008 *
009 * Unless required by applicable law or agreed to in writing, software distributed under the License
010 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
011 * or implied. See the License for the specific language governing permissions and limitations under
012 * the License.
013 */
014
015package com.google.common.util.concurrent;
016
017import com.google.common.annotations.GwtIncompatible;
018import com.google.common.annotations.J2ktIncompatible;
019import com.google.errorprone.annotations.CanIgnoreReturnValue;
020import com.google.errorprone.annotations.CheckReturnValue;
021import java.util.concurrent.AbstractExecutorService;
022import java.util.concurrent.Callable;
023import java.util.concurrent.RunnableFuture;
024import org.checkerframework.checker.nullness.qual.Nullable;
025
026/**
027 * Abstract {@link ListeningExecutorService} implementation that creates {@link ListenableFuture}
028 * instances for each {@link Runnable} and {@link Callable} submitted to it. These tasks are run
029 * with the abstract {@link #execute execute(Runnable)} method.
030 *
031 * <p>In addition to {@link #execute}, subclasses must implement all methods related to shutdown and
032 * termination.
033 *
034 * @author Chris Povirk
035 * @since 14.0
036 */
037@CheckReturnValue
038@GwtIncompatible
039@J2ktIncompatible
040@ElementTypesAreNonnullByDefault
041public abstract class AbstractListeningExecutorService extends AbstractExecutorService
042    implements ListeningExecutorService {
043  /** Constructor for use by subclasses. */
044  public AbstractListeningExecutorService() {}
045
046  /**
047   * @since 19.0 (present with return type {@code ListenableFutureTask} since 14.0)
048   */
049  @CanIgnoreReturnValue // TODO(kak): consider removing this
050  @Override
051  protected final <T extends @Nullable Object> RunnableFuture<T> newTaskFor(
052      Runnable runnable, @ParametricNullness T value) {
053    return TrustedListenableFutureTask.create(runnable, value);
054  }
055
056  /**
057   * @since 19.0 (present with return type {@code ListenableFutureTask} since 14.0)
058   */
059  @CanIgnoreReturnValue // TODO(kak): consider removing this
060  @Override
061  protected final <T extends @Nullable Object> RunnableFuture<T> newTaskFor(Callable<T> callable) {
062    return TrustedListenableFutureTask.create(callable);
063  }
064
065  @CanIgnoreReturnValue // TODO(kak): consider removing this
066  @Override
067  public ListenableFuture<?> submit(Runnable task) {
068    return (ListenableFuture<?>) super.submit(task);
069  }
070
071  @CanIgnoreReturnValue // TODO(kak): consider removing this
072  @Override
073  public <T extends @Nullable Object> ListenableFuture<T> submit(
074      Runnable task, @ParametricNullness T result) {
075    return (ListenableFuture<T>) super.submit(task, result);
076  }
077
078  @CanIgnoreReturnValue // TODO(kak): consider removing this
079  @Override
080  public <T extends @Nullable Object> ListenableFuture<T> submit(Callable<T> task) {
081    return (ListenableFuture<T>) super.submit(task);
082  }
083}