current/sdk/sdk_library/public/art.module.public.api_stub_sources/java/util/concurrent/ExecutorCompletionService.java

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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/*
 * This file is available under and governed by the GNU General Public
 * License version 2 only, as published by the Free Software Foundation.
 * However, the following notice accompanied the original version of this
 * file:
 *
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 */


package java.util.concurrent;


/**
 * A {@link java.util.concurrent.CompletionService CompletionService} that uses a supplied {@link java.util.concurrent.Executor Executor}
 * to execute tasks.  This class arranges that submitted tasks are,
 * upon completion, placed on a queue accessible using {@code take}.
 * The class is lightweight enough to be suitable for transient use
 * when processing groups of tasks.
 *
 * <p>
 *
 * <b>Usage Examples.</b>
 *
 * Suppose you have a set of solvers for a certain problem, each
 * returning a value of some type {@code Result}, and would like to
 * run them concurrently, processing the results of each of them that
 * return a non-null value, in some method {@code use(Result r)}. You
 * could write this as:
 *
 * <pre> {@code
 * void solve(Executor e,
 *            Collection<Callable<Result>> solvers)
 *     throws InterruptedException, ExecutionException {
 *   CompletionService<Result> ecs
 *       = new ExecutorCompletionService<Result>(e);
 *   for (Callable<Result> s : solvers)
 *     ecs.submit(s);
 *   int n = solvers.size();
 *   for (int i = 0; i < n; ++i) {
 *     Result r = ecs.take().get();
 *     if (r != null)
 *       use(r);
 *   }
 * }}</pre>
 *
 * Suppose instead that you would like to use the first non-null result
 * of the set of tasks, ignoring any that encounter exceptions,
 * and cancelling all other tasks when the first one is ready:
 *
 * <pre> {@code
 * void solve(Executor e,
 *            Collection<Callable<Result>> solvers)
 *     throws InterruptedException {
 *   CompletionService<Result> ecs
 *       = new ExecutorCompletionService<Result>(e);
 *   int n = solvers.size();
 *   List<Future<Result>> futures = new ArrayList<>(n);
 *   Result result = null;
 *   try {
 *     for (Callable<Result> s : solvers)
 *       futures.add(ecs.submit(s));
 *     for (int i = 0; i < n; ++i) {
 *       try {
 *         Result r = ecs.take().get();
 *         if (r != null) {
 *           result = r;
 *           break;
 *         }
 *       } catch (ExecutionException ignore) {}
 *     }
 *   }
 *   finally {
 *     for (Future<Result> f : futures)
 *       f.cancel(true);
 *   }
 *
 *   if (result != null)
 *     use(result);
 * }}</pre>
 */

@SuppressWarnings({"unchecked", "deprecation", "all"})
public class ExecutorCompletionService<V> implements java.util.concurrent.CompletionService<V> {

/**
 * Creates an ExecutorCompletionService using the supplied
 * executor for base task execution and a
 * {@link java.util.concurrent.LinkedBlockingQueue LinkedBlockingQueue} as a completion queue.
 *
 * @param executor the executor to use
 * @throws java.lang.NullPointerException if executor is {@code null}
 */

public ExecutorCompletionService(java.util.concurrent.Executor executor) { throw new RuntimeException("Stub!"); }

/**
 * Creates an ExecutorCompletionService using the supplied
 * executor for base task execution and the supplied queue as its
 * completion queue.
 *
 * @param executor the executor to use
 * @param completionQueue the queue to use as the completion queue
 *        normally one dedicated for use by this service. This
 *        queue is treated as unbounded -- failed attempted
 *        {@code Queue.add} operations for completed tasks cause
 *        them not to be retrievable.
 * @throws java.lang.NullPointerException if executor or completionQueue are {@code null}
 */

public ExecutorCompletionService(java.util.concurrent.Executor executor, java.util.concurrent.BlockingQueue<java.util.concurrent.Future<V>> completionQueue) { throw new RuntimeException("Stub!"); }

public java.util.concurrent.Future<V> submit(java.util.concurrent.Callable<V> task) { throw new RuntimeException("Stub!"); }

public java.util.concurrent.Future<V> submit(java.lang.Runnable task, V result) { throw new RuntimeException("Stub!"); }

public java.util.concurrent.Future<V> take() throws java.lang.InterruptedException { throw new RuntimeException("Stub!"); }

public java.util.concurrent.Future<V> poll() { throw new RuntimeException("Stub!"); }

public java.util.concurrent.Future<V> poll(long timeout, java.util.concurrent.TimeUnit unit) throws java.lang.InterruptedException { throw new RuntimeException("Stub!"); }
}