| /* |
| * 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 |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * 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; |
| |
| import java.time.Duration; |
| import java.time.temporal.ChronoUnit; |
| import java.util.Objects; |
| |
| /** |
| * A {@code TimeUnit} represents time durations at a given unit of |
| * granularity and provides utility methods to convert across units, |
| * and to perform timing and delay operations in these units. A |
| * {@code TimeUnit} does not maintain time information, but only |
| * helps organize and use time representations that may be maintained |
| * separately across various contexts. A nanosecond is defined as one |
| * thousandth of a microsecond, a microsecond as one thousandth of a |
| * millisecond, a millisecond as one thousandth of a second, a minute |
| * as sixty seconds, an hour as sixty minutes, and a day as twenty four |
| * hours. |
| * |
| * <p>A {@code TimeUnit} is mainly used to inform time-based methods |
| * how a given timing parameter should be interpreted. For example, |
| * the following code will timeout in 50 milliseconds if the {@link |
| * java.util.concurrent.locks.Lock lock} is not available: |
| * |
| * <pre> {@code |
| * Lock lock = ...; |
| * if (lock.tryLock(50L, TimeUnit.MILLISECONDS)) ...}</pre> |
| * |
| * while this code will timeout in 50 seconds: |
| * <pre> {@code |
| * Lock lock = ...; |
| * if (lock.tryLock(50L, TimeUnit.SECONDS)) ...}</pre> |
| * |
| * Note however, that there is no guarantee that a particular timeout |
| * implementation will be able to notice the passage of time at the |
| * same granularity as the given {@code TimeUnit}. |
| * |
| * @since 1.5 |
| * @author Doug Lea |
| */ |
| public enum TimeUnit { |
| /** |
| * Time unit representing one thousandth of a microsecond. |
| */ |
| NANOSECONDS(TimeUnit.NANO_SCALE), |
| /** |
| * Time unit representing one thousandth of a millisecond. |
| */ |
| MICROSECONDS(TimeUnit.MICRO_SCALE), |
| /** |
| * Time unit representing one thousandth of a second. |
| */ |
| MILLISECONDS(TimeUnit.MILLI_SCALE), |
| /** |
| * Time unit representing one second. |
| */ |
| SECONDS(TimeUnit.SECOND_SCALE), |
| /** |
| * Time unit representing sixty seconds. |
| * @since 1.6 |
| */ |
| MINUTES(TimeUnit.MINUTE_SCALE), |
| /** |
| * Time unit representing sixty minutes. |
| * @since 1.6 |
| */ |
| HOURS(TimeUnit.HOUR_SCALE), |
| /** |
| * Time unit representing twenty four hours. |
| * @since 1.6 |
| */ |
| DAYS(TimeUnit.DAY_SCALE); |
| |
| // Scales as constants |
| private static final long NANO_SCALE = 1L; |
| private static final long MICRO_SCALE = 1000L * NANO_SCALE; |
| private static final long MILLI_SCALE = 1000L * MICRO_SCALE; |
| private static final long SECOND_SCALE = 1000L * MILLI_SCALE; |
| private static final long MINUTE_SCALE = 60L * SECOND_SCALE; |
| private static final long HOUR_SCALE = 60L * MINUTE_SCALE; |
| private static final long DAY_SCALE = 24L * HOUR_SCALE; |
| |
| /* |
| * Instances cache conversion ratios and saturation cutoffs for |
| * the units up through SECONDS. Other cases compute them, in |
| * method cvt. |
| */ |
| |
| private final long scale; |
| private final long maxNanos; |
| private final long maxMicros; |
| private final long maxMillis; |
| private final long maxSecs; |
| private final long microRatio; |
| private final int milliRatio; // fits in 32 bits |
| private final int secRatio; // fits in 32 bits |
| |
| private TimeUnit(long s) { |
| this.scale = s; |
| this.maxNanos = Long.MAX_VALUE / s; |
| long ur = (s >= MICRO_SCALE) ? (s / MICRO_SCALE) : (MICRO_SCALE / s); |
| this.microRatio = ur; |
| this.maxMicros = Long.MAX_VALUE / ur; |
| long mr = (s >= MILLI_SCALE) ? (s / MILLI_SCALE) : (MILLI_SCALE / s); |
| this.milliRatio = (int)mr; |
| this.maxMillis = Long.MAX_VALUE / mr; |
| long sr = (s >= SECOND_SCALE) ? (s / SECOND_SCALE) : (SECOND_SCALE / s); |
| this.secRatio = (int)sr; |
| this.maxSecs = Long.MAX_VALUE / sr; |
| } |
| |
| /** |
| * General conversion utility. |
| * |
| * @param d duration |
| * @param dst result unit scale |
| * @param src source unit scale |
| */ |
| private static long cvt(long d, long dst, long src) { |
| long r, m; |
| if (src == dst) |
| return d; |
| else if (src < dst) |
| return d / (dst / src); |
| else if (d > (m = Long.MAX_VALUE / (r = src / dst))) |
| return Long.MAX_VALUE; |
| else if (d < -m) |
| return Long.MIN_VALUE; |
| else |
| return d * r; |
| } |
| |
| /** |
| * Converts the given time duration in the given unit to this unit. |
| * Conversions from finer to coarser granularities truncate, so |
| * lose precision. For example, converting {@code 999} milliseconds |
| * to seconds results in {@code 0}. Conversions from coarser to |
| * finer granularities with arguments that would numerically |
| * overflow saturate to {@code Long.MIN_VALUE} if negative or |
| * {@code Long.MAX_VALUE} if positive. |
| * |
| * <p>For example, to convert 10 minutes to milliseconds, use: |
| * {@code TimeUnit.MILLISECONDS.convert(10L, TimeUnit.MINUTES)} |
| * |
| * @param sourceDuration the time duration in the given {@code sourceUnit} |
| * @param sourceUnit the unit of the {@code sourceDuration} argument |
| * @return the converted duration in this unit, |
| * or {@code Long.MIN_VALUE} if conversion would negatively overflow, |
| * or {@code Long.MAX_VALUE} if it would positively overflow. |
| */ |
| public long convert(long sourceDuration, TimeUnit sourceUnit) { |
| switch (this) { |
| case NANOSECONDS: return sourceUnit.toNanos(sourceDuration); |
| case MICROSECONDS: return sourceUnit.toMicros(sourceDuration); |
| case MILLISECONDS: return sourceUnit.toMillis(sourceDuration); |
| case SECONDS: return sourceUnit.toSeconds(sourceDuration); |
| default: return cvt(sourceDuration, scale, sourceUnit.scale); |
| } |
| } |
| |
| /** |
| * Converts the given time duration to this unit. |
| * |
| * <p>For any TimeUnit {@code unit}, |
| * {@code unit.convert(Duration.ofNanos(n))} |
| * is equivalent to |
| * {@code unit.convert(n, NANOSECONDS)}, and |
| * {@code unit.convert(Duration.of(n, unit.toChronoUnit()))} |
| * is equivalent to {@code n} (in the absence of overflow). |
| * |
| * @apiNote |
| * This method differs from {@link Duration#toNanos()} in that it |
| * does not throw {@link ArithmeticException} on numeric overflow. |
| * |
| * @param duration the time duration |
| * @return the converted duration in this unit, |
| * or {@code Long.MIN_VALUE} if conversion would negatively overflow, |
| * or {@code Long.MAX_VALUE} if it would positively overflow. |
| * @throws NullPointerException if {@code duration} is null |
| * @see Duration#of(long,TemporalUnit) |
| * @since 11 |
| */ |
| public long convert(Duration duration) { |
| long secs = duration.getSeconds(); |
| int nano = duration.getNano(); |
| if (secs < 0 && nano > 0) { |
| // use representation compatible with integer division |
| secs++; |
| nano -= (int) SECOND_SCALE; |
| } |
| final long s, nanoVal; |
| // Optimize for the common case - NANOSECONDS without overflow |
| if (this == NANOSECONDS) |
| nanoVal = nano; |
| else if ((s = scale) < SECOND_SCALE) |
| nanoVal = nano / s; |
| else if (this == SECONDS) |
| return secs; |
| else |
| return secs / secRatio; |
| long val = secs * secRatio + nanoVal; |
| return ((secs < maxSecs && secs > -maxSecs) || |
| (secs == maxSecs && val > 0) || |
| (secs == -maxSecs && val < 0)) |
| ? val |
| : (secs > 0) ? Long.MAX_VALUE : Long.MIN_VALUE; |
| } |
| |
| /** |
| * Equivalent to |
| * {@link #convert(long, TimeUnit) NANOSECONDS.convert(duration, this)}. |
| * @param duration the duration |
| * @return the converted duration, |
| * or {@code Long.MIN_VALUE} if conversion would negatively overflow, |
| * or {@code Long.MAX_VALUE} if it would positively overflow. |
| */ |
| public long toNanos(long duration) { |
| long s, m; |
| if ((s = scale) == NANO_SCALE) |
| return duration; |
| else if (duration > (m = maxNanos)) |
| return Long.MAX_VALUE; |
| else if (duration < -m) |
| return Long.MIN_VALUE; |
| else |
| return duration * s; |
| } |
| |
| /** |
| * Equivalent to |
| * {@link #convert(long, TimeUnit) MICROSECONDS.convert(duration, this)}. |
| * @param duration the duration |
| * @return the converted duration, |
| * or {@code Long.MIN_VALUE} if conversion would negatively overflow, |
| * or {@code Long.MAX_VALUE} if it would positively overflow. |
| */ |
| public long toMicros(long duration) { |
| long s, m; |
| if ((s = scale) <= MICRO_SCALE) |
| return (s == MICRO_SCALE) ? duration : duration / microRatio; |
| else if (duration > (m = maxMicros)) |
| return Long.MAX_VALUE; |
| else if (duration < -m) |
| return Long.MIN_VALUE; |
| else |
| return duration * microRatio; |
| } |
| |
| /** |
| * Equivalent to |
| * {@link #convert(long, TimeUnit) MILLISECONDS.convert(duration, this)}. |
| * @param duration the duration |
| * @return the converted duration, |
| * or {@code Long.MIN_VALUE} if conversion would negatively overflow, |
| * or {@code Long.MAX_VALUE} if it would positively overflow. |
| */ |
| public long toMillis(long duration) { |
| long s, m; |
| if ((s = scale) <= MILLI_SCALE) |
| return (s == MILLI_SCALE) ? duration : duration / milliRatio; |
| else if (duration > (m = maxMillis)) |
| return Long.MAX_VALUE; |
| else if (duration < -m) |
| return Long.MIN_VALUE; |
| else |
| return duration * milliRatio; |
| } |
| |
| /** |
| * Equivalent to |
| * {@link #convert(long, TimeUnit) SECONDS.convert(duration, this)}. |
| * @param duration the duration |
| * @return the converted duration, |
| * or {@code Long.MIN_VALUE} if conversion would negatively overflow, |
| * or {@code Long.MAX_VALUE} if it would positively overflow. |
| */ |
| public long toSeconds(long duration) { |
| long s, m; |
| if ((s = scale) <= SECOND_SCALE) |
| return (s == SECOND_SCALE) ? duration : duration / secRatio; |
| else if (duration > (m = maxSecs)) |
| return Long.MAX_VALUE; |
| else if (duration < -m) |
| return Long.MIN_VALUE; |
| else |
| return duration * secRatio; |
| } |
| |
| /** |
| * Equivalent to |
| * {@link #convert(long, TimeUnit) MINUTES.convert(duration, this)}. |
| * @param duration the duration |
| * @return the converted duration, |
| * or {@code Long.MIN_VALUE} if conversion would negatively overflow, |
| * or {@code Long.MAX_VALUE} if it would positively overflow. |
| * @since 1.6 |
| */ |
| public long toMinutes(long duration) { |
| return cvt(duration, MINUTE_SCALE, scale); |
| } |
| |
| /** |
| * Equivalent to |
| * {@link #convert(long, TimeUnit) HOURS.convert(duration, this)}. |
| * @param duration the duration |
| * @return the converted duration, |
| * or {@code Long.MIN_VALUE} if conversion would negatively overflow, |
| * or {@code Long.MAX_VALUE} if it would positively overflow. |
| * @since 1.6 |
| */ |
| public long toHours(long duration) { |
| return cvt(duration, HOUR_SCALE, scale); |
| } |
| |
| /** |
| * Equivalent to |
| * {@link #convert(long, TimeUnit) DAYS.convert(duration, this)}. |
| * @param duration the duration |
| * @return the converted duration |
| * @since 1.6 |
| */ |
| public long toDays(long duration) { |
| return cvt(duration, DAY_SCALE, scale); |
| } |
| |
| /** |
| * Utility to compute the excess-nanosecond argument to wait, |
| * sleep, join. |
| * @param d the duration |
| * @param m the number of milliseconds |
| * @return the number of nanoseconds |
| */ |
| private int excessNanos(long d, long m) { |
| long s; |
| if ((s = scale) == NANO_SCALE) |
| return (int)(d - (m * MILLI_SCALE)); |
| else if (s == MICRO_SCALE) |
| return (int)((d * 1000L) - (m * MILLI_SCALE)); |
| else |
| return 0; |
| } |
| |
| /** |
| * Performs a timed {@link Object#wait(long, int) Object.wait} |
| * using this time unit. |
| * This is a convenience method that converts timeout arguments |
| * into the form required by the {@code Object.wait} method. |
| * |
| * <p>For example, you could implement a blocking {@code poll} method |
| * (see {@link BlockingQueue#poll(long, TimeUnit) BlockingQueue.poll}) |
| * using: |
| * |
| * <pre> {@code |
| * public E poll(long timeout, TimeUnit unit) |
| * throws InterruptedException { |
| * synchronized (lock) { |
| * while (isEmpty()) { |
| * unit.timedWait(lock, timeout); |
| * ... |
| * } |
| * } |
| * }}</pre> |
| * |
| * @param obj the object to wait on |
| * @param timeout the maximum time to wait. If less than |
| * or equal to zero, do not wait at all. |
| * @throws InterruptedException if interrupted while waiting |
| */ |
| public void timedWait(Object obj, long timeout) |
| throws InterruptedException { |
| if (timeout > 0) { |
| long ms = toMillis(timeout); |
| int ns = excessNanos(timeout, ms); |
| obj.wait(ms, ns); |
| } |
| } |
| |
| /** |
| * Performs a timed {@link Thread#join(long, int) Thread.join} |
| * using this time unit. |
| * This is a convenience method that converts time arguments into the |
| * form required by the {@code Thread.join} method. |
| * |
| * @param thread the thread to wait for |
| * @param timeout the maximum time to wait. If less than |
| * or equal to zero, do not wait at all. |
| * @throws InterruptedException if interrupted while waiting |
| */ |
| public void timedJoin(Thread thread, long timeout) |
| throws InterruptedException { |
| if (timeout > 0) { |
| long ms = toMillis(timeout); |
| int ns = excessNanos(timeout, ms); |
| thread.join(ms, ns); |
| } |
| } |
| |
| /** |
| * Performs a {@link Thread#sleep(long, int) Thread.sleep} using |
| * this time unit. |
| * This is a convenience method that converts time arguments into the |
| * form required by the {@code Thread.sleep} method. |
| * |
| * @param timeout the minimum time to sleep. If less than |
| * or equal to zero, do not sleep at all. |
| * @throws InterruptedException if interrupted while sleeping |
| */ |
| public void sleep(long timeout) throws InterruptedException { |
| if (timeout > 0) { |
| long ms = toMillis(timeout); |
| int ns = excessNanos(timeout, ms); |
| Thread.sleep(ms, ns); |
| } |
| } |
| |
| /** |
| * Converts this {@code TimeUnit} to the equivalent {@code ChronoUnit}. |
| * |
| * @return the converted equivalent ChronoUnit |
| * @since 9 |
| */ |
| public ChronoUnit toChronoUnit() { |
| switch (this) { |
| case NANOSECONDS: return ChronoUnit.NANOS; |
| case MICROSECONDS: return ChronoUnit.MICROS; |
| case MILLISECONDS: return ChronoUnit.MILLIS; |
| case SECONDS: return ChronoUnit.SECONDS; |
| case MINUTES: return ChronoUnit.MINUTES; |
| case HOURS: return ChronoUnit.HOURS; |
| case DAYS: return ChronoUnit.DAYS; |
| default: throw new AssertionError(); |
| } |
| } |
| |
| /** |
| * Converts a {@code ChronoUnit} to the equivalent {@code TimeUnit}. |
| * |
| * @param chronoUnit the ChronoUnit to convert |
| * @return the converted equivalent TimeUnit |
| * @throws IllegalArgumentException if {@code chronoUnit} has no |
| * equivalent TimeUnit |
| * @throws NullPointerException if {@code chronoUnit} is null |
| * @since 9 |
| */ |
| public static TimeUnit of(ChronoUnit chronoUnit) { |
| switch (Objects.requireNonNull(chronoUnit, "chronoUnit")) { |
| case NANOS: return TimeUnit.NANOSECONDS; |
| case MICROS: return TimeUnit.MICROSECONDS; |
| case MILLIS: return TimeUnit.MILLISECONDS; |
| case SECONDS: return TimeUnit.SECONDS; |
| case MINUTES: return TimeUnit.MINUTES; |
| case HOURS: return TimeUnit.HOURS; |
| case DAYS: return TimeUnit.DAYS; |
| default: |
| throw new IllegalArgumentException( |
| "No TimeUnit equivalent for " + chronoUnit); |
| } |
| } |
| |
| } |