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 static java.util.concurrent.TimeUnit.NANOSECONDS;
018
019import com.google.common.annotations.GwtCompatible;
020import com.google.common.annotations.GwtIncompatible;
021import com.google.common.base.Preconditions;
022import com.google.errorprone.annotations.CanIgnoreReturnValue;
023import java.util.concurrent.BlockingQueue;
024import java.util.concurrent.CancellationException;
025import java.util.concurrent.CountDownLatch;
026import java.util.concurrent.ExecutionException;
027import java.util.concurrent.Future;
028import java.util.concurrent.Semaphore;
029import java.util.concurrent.TimeUnit;
030import java.util.concurrent.TimeoutException;
031import java.util.concurrent.locks.Condition;
032
033/**
034 * Utilities for treating interruptible operations as uninterruptible. In all cases, if a thread is
035 * interrupted during such a call, the call continues to block until the result is available or the
036 * timeout elapses, and only then re-interrupts the thread.
037 *
038 * @author Anthony Zana
039 * @since 10.0
040 */
041@GwtCompatible(emulated = true)
042public final class Uninterruptibles {
043
044  // Implementation Note: As of 3-7-11, the logic for each blocking/timeout
045  // methods is identical, save for method being invoked.
046
047  /** Invokes {@code latch.}{@link CountDownLatch#await() await()} uninterruptibly. */
048  @GwtIncompatible // concurrency
049  public static void awaitUninterruptibly(CountDownLatch latch) {
050    boolean interrupted = false;
051    try {
052      while (true) {
053        try {
054          latch.await();
055          return;
056        } catch (InterruptedException e) {
057          interrupted = true;
058        }
059      }
060    } finally {
061      if (interrupted) {
062        Thread.currentThread().interrupt();
063      }
064    }
065  }
066
067  /**
068   * Invokes {@code latch.}{@link CountDownLatch#await(long, TimeUnit) await(timeout, unit)}
069   * uninterruptibly.
070   */
071  @CanIgnoreReturnValue // TODO(cpovirk): Consider being more strict.
072  @GwtIncompatible // concurrency
073  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
074  public static boolean awaitUninterruptibly(CountDownLatch latch, long timeout, TimeUnit unit) {
075    boolean interrupted = false;
076    try {
077      long remainingNanos = unit.toNanos(timeout);
078      long end = System.nanoTime() + remainingNanos;
079
080      while (true) {
081        try {
082          // CountDownLatch treats negative timeouts just like zero.
083          return latch.await(remainingNanos, NANOSECONDS);
084        } catch (InterruptedException e) {
085          interrupted = true;
086          remainingNanos = end - System.nanoTime();
087        }
088      }
089    } finally {
090      if (interrupted) {
091        Thread.currentThread().interrupt();
092      }
093    }
094  }
095
096  /**
097   * Invokes {@code condition.}{@link Condition#await(long, TimeUnit) await(timeout, unit)}
098   * uninterruptibly.
099   *
100   * @since 23.6
101   */
102  @GwtIncompatible // concurrency
103  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
104  public static boolean awaitUninterruptibly(Condition condition, long timeout, TimeUnit unit) {
105    boolean interrupted = false;
106    try {
107      long remainingNanos = unit.toNanos(timeout);
108      long end = System.nanoTime() + remainingNanos;
109
110      while (true) {
111        try {
112          return condition.await(remainingNanos, NANOSECONDS);
113        } catch (InterruptedException e) {
114          interrupted = true;
115          remainingNanos = end - System.nanoTime();
116        }
117      }
118    } finally {
119      if (interrupted) {
120        Thread.currentThread().interrupt();
121      }
122    }
123  }
124
125  /** Invokes {@code toJoin.}{@link Thread#join() join()} uninterruptibly. */
126  @GwtIncompatible // concurrency
127  public static void joinUninterruptibly(Thread toJoin) {
128    boolean interrupted = false;
129    try {
130      while (true) {
131        try {
132          toJoin.join();
133          return;
134        } catch (InterruptedException e) {
135          interrupted = true;
136        }
137      }
138    } finally {
139      if (interrupted) {
140        Thread.currentThread().interrupt();
141      }
142    }
143  }
144
145  /**
146   * Invokes {@code unit.}{@link TimeUnit#timedJoin(Thread, long) timedJoin(toJoin, timeout)}
147   * uninterruptibly.
148   */
149  @GwtIncompatible // concurrency
150  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
151  public static void joinUninterruptibly(Thread toJoin, long timeout, TimeUnit unit) {
152    Preconditions.checkNotNull(toJoin);
153    boolean interrupted = false;
154    try {
155      long remainingNanos = unit.toNanos(timeout);
156      long end = System.nanoTime() + remainingNanos;
157      while (true) {
158        try {
159          // TimeUnit.timedJoin() treats negative timeouts just like zero.
160          NANOSECONDS.timedJoin(toJoin, remainingNanos);
161          return;
162        } catch (InterruptedException e) {
163          interrupted = true;
164          remainingNanos = end - System.nanoTime();
165        }
166      }
167    } finally {
168      if (interrupted) {
169        Thread.currentThread().interrupt();
170      }
171    }
172  }
173
174  /**
175   * Invokes {@code future.}{@link Future#get() get()} uninterruptibly.
176   *
177   * <p>Similar methods:
178   *
179   * <ul>
180   *   <li>To retrieve a result from a {@code Future} that is already done, use {@link
181   *       Futures#getDone Futures.getDone}.
182   *   <li>To treat {@link InterruptedException} uniformly with other exceptions, use {@link
183   *       Futures#getChecked(Future, Class) Futures.getChecked}.
184   *   <li>To get uninterruptibility and remove checked exceptions, use {@link
185   *       Futures#getUnchecked}.
186   * </ul>
187   *
188   * @throws ExecutionException if the computation threw an exception
189   * @throws CancellationException if the computation was cancelled
190   */
191  @CanIgnoreReturnValue
192  public static <V> V getUninterruptibly(Future<V> future) throws ExecutionException {
193    boolean interrupted = false;
194    try {
195      while (true) {
196        try {
197          return future.get();
198        } catch (InterruptedException e) {
199          interrupted = true;
200        }
201      }
202    } finally {
203      if (interrupted) {
204        Thread.currentThread().interrupt();
205      }
206    }
207  }
208
209  /**
210   * Invokes {@code future.}{@link Future#get(long, TimeUnit) get(timeout, unit)} uninterruptibly.
211   *
212   * <p>Similar methods:
213   *
214   * <ul>
215   *   <li>To retrieve a result from a {@code Future} that is already done, use {@link
216   *       Futures#getDone Futures.getDone}.
217   *   <li>To treat {@link InterruptedException} uniformly with other exceptions, use {@link
218   *       Futures#getChecked(Future, Class, long, TimeUnit) Futures.getChecked}.
219   *   <li>To get uninterruptibility and remove checked exceptions, use {@link
220   *       Futures#getUnchecked}.
221   * </ul>
222   *
223   * @throws ExecutionException if the computation threw an exception
224   * @throws CancellationException if the computation was cancelled
225   * @throws TimeoutException if the wait timed out
226   */
227  @CanIgnoreReturnValue
228  @GwtIncompatible // TODO
229  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
230  public static <V> V getUninterruptibly(Future<V> future, long timeout, TimeUnit unit)
231      throws ExecutionException, TimeoutException {
232    boolean interrupted = false;
233    try {
234      long remainingNanos = unit.toNanos(timeout);
235      long end = System.nanoTime() + remainingNanos;
236
237      while (true) {
238        try {
239          // Future treats negative timeouts just like zero.
240          return future.get(remainingNanos, NANOSECONDS);
241        } catch (InterruptedException e) {
242          interrupted = true;
243          remainingNanos = end - System.nanoTime();
244        }
245      }
246    } finally {
247      if (interrupted) {
248        Thread.currentThread().interrupt();
249      }
250    }
251  }
252
253  /** Invokes {@code queue.}{@link BlockingQueue#take() take()} uninterruptibly. */
254  @GwtIncompatible // concurrency
255  public static <E> E takeUninterruptibly(BlockingQueue<E> queue) {
256    boolean interrupted = false;
257    try {
258      while (true) {
259        try {
260          return queue.take();
261        } catch (InterruptedException e) {
262          interrupted = true;
263        }
264      }
265    } finally {
266      if (interrupted) {
267        Thread.currentThread().interrupt();
268      }
269    }
270  }
271
272  /**
273   * Invokes {@code queue.}{@link BlockingQueue#put(Object) put(element)} uninterruptibly.
274   *
275   * @throws ClassCastException if the class of the specified element prevents it from being added
276   *     to the given queue
277   * @throws IllegalArgumentException if some property of the specified element prevents it from
278   *     being added to the given queue
279   */
280  @GwtIncompatible // concurrency
281  public static <E> void putUninterruptibly(BlockingQueue<E> queue, E element) {
282    boolean interrupted = false;
283    try {
284      while (true) {
285        try {
286          queue.put(element);
287          return;
288        } catch (InterruptedException e) {
289          interrupted = true;
290        }
291      }
292    } finally {
293      if (interrupted) {
294        Thread.currentThread().interrupt();
295      }
296    }
297  }
298
299  // TODO(user): Support Sleeper somehow (wrapper or interface method)?
300  /** Invokes {@code unit.}{@link TimeUnit#sleep(long) sleep(sleepFor)} uninterruptibly. */
301  @GwtIncompatible // concurrency
302  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
303  public static void sleepUninterruptibly(long sleepFor, TimeUnit unit) {
304    boolean interrupted = false;
305    try {
306      long remainingNanos = unit.toNanos(sleepFor);
307      long end = System.nanoTime() + remainingNanos;
308      while (true) {
309        try {
310          // TimeUnit.sleep() treats negative timeouts just like zero.
311          NANOSECONDS.sleep(remainingNanos);
312          return;
313        } catch (InterruptedException e) {
314          interrupted = true;
315          remainingNanos = end - System.nanoTime();
316        }
317      }
318    } finally {
319      if (interrupted) {
320        Thread.currentThread().interrupt();
321      }
322    }
323  }
324
325  /**
326   * Invokes {@code semaphore.}{@link Semaphore#tryAcquire(int, long, TimeUnit) tryAcquire(1,
327   * timeout, unit)} uninterruptibly.
328   *
329   * @since 18.0
330   */
331  @GwtIncompatible // concurrency
332  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
333  public static boolean tryAcquireUninterruptibly(
334      Semaphore semaphore, long timeout, TimeUnit unit) {
335    return tryAcquireUninterruptibly(semaphore, 1, timeout, unit);
336  }
337
338  /**
339   * Invokes {@code semaphore.}{@link Semaphore#tryAcquire(int, long, TimeUnit) tryAcquire(permits,
340   * timeout, unit)} uninterruptibly.
341   *
342   * @since 18.0
343   */
344  @GwtIncompatible // concurrency
345  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
346  public static boolean tryAcquireUninterruptibly(
347      Semaphore semaphore, int permits, long timeout, TimeUnit unit) {
348    boolean interrupted = false;
349    try {
350      long remainingNanos = unit.toNanos(timeout);
351      long end = System.nanoTime() + remainingNanos;
352
353      while (true) {
354        try {
355          // Semaphore treats negative timeouts just like zero.
356          return semaphore.tryAcquire(permits, remainingNanos, NANOSECONDS);
357        } catch (InterruptedException e) {
358          interrupted = true;
359          remainingNanos = end - System.nanoTime();
360        }
361      }
362    } finally {
363      if (interrupted) {
364        Thread.currentThread().interrupt();
365      }
366    }
367  }
368
369  // TODO(user): Add support for waitUninterruptibly.
370
371  private Uninterruptibles() {}
372}