util/concurrent/TimeUnit.java

/*
 * 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).
     *
     * <p>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);
        }
    }

}
Revision:	1.66
Committed:	Sun Jun 10 01:18:10 2018 UTC (5 years, 11 months ago) by jsr166
Branch:	MAIN
Changes since 1.65:	+1 -1 lines
Log Message:	suppress errorprone [NarrowingCompoundAssignment] warning
#	User	Rev	Content
1	dl	1.2	/*
2	jsr166	1.35	* Written by Doug Lea with assistance from members of JCP JSR-166
3			* Expert Group and released to the public domain, as explained at
4	jsr166	1.38	* http://creativecommons.org/publicdomain/zero/1.0/
5	jsr166	1.35	*/
6	dl	1.2
7	tim	1.1	package java.util.concurrent;
8
9	jsr166	1.64	import java.time.Duration;
10	jsr166	1.48	import java.time.temporal.ChronoUnit;
11			import java.util.Objects;
12
13	tim	1.1	/**
14	jsr166	1.40	* A {@code TimeUnit} represents time durations at a given unit of
15	dl	1.27	* granularity and provides utility methods to convert across units,
16			* and to perform timing and delay operations in these units. A
17	jsr166	1.40	* {@code TimeUnit} does not maintain time information, but only
18	dl	1.27	* helps organize and use time representations that may be maintained
19			* separately across various contexts. A nanosecond is defined as one
20			* thousandth of a microsecond, a microsecond as one thousandth of a
21			* millisecond, a millisecond as one thousandth of a second, a minute
22			* as sixty seconds, an hour as sixty minutes, and a day as twenty four
23			* hours.
24			*
25	jsr166	1.40	* <p>A {@code TimeUnit} is mainly used to inform time-based methods
26	dl	1.27	* how a given timing parameter should be interpreted. For example,
27			* the following code will timeout in 50 milliseconds if the {@link
28			* java.util.concurrent.locks.Lock lock} is not available:
29			*
30	jsr166	1.45	* <pre> {@code
31	jsr166	1.39	* Lock lock = ...;
32			* if (lock.tryLock(50L, TimeUnit.MILLISECONDS)) ...}</pre>
33			*
34	dl	1.27	* while this code will timeout in 50 seconds:
35	jsr166	1.45	* <pre> {@code
36	jsr166	1.39	* Lock lock = ...;
37			* if (lock.tryLock(50L, TimeUnit.SECONDS)) ...}</pre>
38	dl	1.27	*
39			* Note however, that there is no guarantee that a particular timeout
40			* implementation will be able to notice the passage of time at the
41	jsr166	1.40	* same granularity as the given {@code TimeUnit}.
42	dl	1.27	*
43			* @since 1.5
44			* @author Doug Lea
45			*/
46	dl	1.20	public enum TimeUnit {
47	jsr166	1.43	/**
48	jsr166	1.47	* Time unit representing one thousandth of a microsecond.
49	jsr166	1.43	*/
50	jsr166	1.56	NANOSECONDS(TimeUnit.NANO_SCALE),
51	jsr166	1.43	/**
52	jsr166	1.47	* Time unit representing one thousandth of a millisecond.
53	jsr166	1.43	*/
54	jsr166	1.56	MICROSECONDS(TimeUnit.MICRO_SCALE),
55	jsr166	1.43	/**
56	jsr166	1.47	* Time unit representing one thousandth of a second.
57	jsr166	1.43	*/
58	jsr166	1.56	MILLISECONDS(TimeUnit.MILLI_SCALE),
59	jsr166	1.43	/**
60	jsr166	1.47	* Time unit representing one second.
61	jsr166	1.43	*/
62	jsr166	1.56	SECONDS(TimeUnit.SECOND_SCALE),
63	jsr166	1.43	/**
64	jsr166	1.47	* Time unit representing sixty seconds.
65	jsr166	1.44	* @since 1.6
66	jsr166	1.43	*/
67	jsr166	1.56	MINUTES(TimeUnit.MINUTE_SCALE),
68	jsr166	1.43	/**
69	jsr166	1.47	* Time unit representing sixty minutes.
70	jsr166	1.44	* @since 1.6
71	jsr166	1.43	*/
72	jsr166	1.56	HOURS(TimeUnit.HOUR_SCALE),
73	jsr166	1.43	/**
74	jsr166	1.47	* Time unit representing twenty four hours.
75	jsr166	1.44	* @since 1.6
76	jsr166	1.43	*/
77	jsr166	1.56	DAYS(TimeUnit.DAY_SCALE);
78	dl	1.49
79			// Scales as constants
80			private static final long NANO_SCALE = 1L;
81			private static final long MICRO_SCALE = 1000L * NANO_SCALE;
82			private static final long MILLI_SCALE = 1000L * MICRO_SCALE;
83			private static final long SECOND_SCALE = 1000L * MILLI_SCALE;
84			private static final long MINUTE_SCALE = 60L * SECOND_SCALE;
85			private static final long HOUR_SCALE = 60L * MINUTE_SCALE;
86			private static final long DAY_SCALE = 24L * HOUR_SCALE;
87
88			/*
89			* Instances cache conversion ratios and saturation cutoffs for
90	dl	1.53	* the units up through SECONDS. Other cases compute them, in
91	dl	1.52	* method cvt.
92	dl	1.49	*/
93
94			private final long scale;
95			private final long maxNanos;
96	dl	1.53	private final long maxMicros;
97	dl	1.49	private final long maxMillis;
98	dl	1.52	private final long maxSecs;
99	dl	1.53	private final long microRatio;
100			private final int milliRatio; // fits in 32 bits
101			private final int secRatio; // fits in 32 bits
102
103	jsr166	1.59	private TimeUnit(long s) {
104	dl	1.53	this.scale = s;
105			this.maxNanos = Long.MAX_VALUE / s;
106			long ur = (s >= MICRO_SCALE) ? (s / MICRO_SCALE) : (MICRO_SCALE / s);
107			this.microRatio = ur;
108			this.maxMicros = Long.MAX_VALUE / ur;
109	jsr166	1.55	long mr = (s >= MILLI_SCALE) ? (s / MILLI_SCALE) : (MILLI_SCALE / s);
110	dl	1.52	this.milliRatio = (int)mr;
111			this.maxMillis = Long.MAX_VALUE / mr;
112	dl	1.53	long sr = (s >= SECOND_SCALE) ? (s / SECOND_SCALE) : (SECOND_SCALE / s);
113	dl	1.52	this.secRatio = (int)sr;
114			this.maxSecs = Long.MAX_VALUE / sr;
115	dl	1.49	}
116
117			/**
118			* General conversion utility.
119			*
120			* @param d duration
121	jsr166	1.57	* @param dst result unit scale
122			* @param src source unit scale
123	dl	1.49	*/
124			private static long cvt(long d, long dst, long src) {
125			long r, m;
126	dl	1.50	if (src == dst)
127			return d;
128			else if (src < dst)
129			return d / (dst / src);
130			else if (d > (m = Long.MAX_VALUE / (r = src / dst)))
131			return Long.MAX_VALUE;
132			else if (d < -m)
133			return Long.MIN_VALUE;
134			else
135			return d * r;
136	dl	1.49	}
137	dl	1.32
138	dl	1.27	/**
139	jsr166	1.42	* Converts the given time duration in the given unit to this unit.
140			* Conversions from finer to coarser granularities truncate, so
141			* lose precision. For example, converting {@code 999} milliseconds
142			* to seconds results in {@code 0}. Conversions from coarser to
143			* finer granularities with arguments that would numerically
144			* overflow saturate to {@code Long.MIN_VALUE} if negative or
145			* {@code Long.MAX_VALUE} if positive.
146	jsr166	1.33	*
147			* <p>For example, to convert 10 minutes to milliseconds, use:
148	jsr166	1.40	* {@code TimeUnit.MILLISECONDS.convert(10L, TimeUnit.MINUTES)}
149	dl	1.27	*
150	jsr166	1.40	* @param sourceDuration the time duration in the given {@code sourceUnit}
151			* @param sourceUnit the unit of the {@code sourceDuration} argument
152	dl	1.27	* @return the converted duration in this unit,
153	jsr166	1.58	* or {@code Long.MIN_VALUE} if conversion would negatively overflow,
154			* or {@code Long.MAX_VALUE} if it would positively overflow.
155	dl	1.27	*/
156	dl	1.32	public long convert(long sourceDuration, TimeUnit sourceUnit) {
157	dl	1.53	switch (this) {
158	jsr166	1.54	case NANOSECONDS: return sourceUnit.toNanos(sourceDuration);
159	dl	1.53	case MICROSECONDS: return sourceUnit.toMicros(sourceDuration);
160			case MILLISECONDS: return sourceUnit.toMillis(sourceDuration);
161	jsr166	1.54	case SECONDS: return sourceUnit.toSeconds(sourceDuration);
162	dl	1.53	default: return cvt(sourceDuration, scale, sourceUnit.scale);
163			}
164	dl	1.32	}
165	jsr166	1.29
166	dl	1.27	/**
167	jsr166	1.64	* Converts the given time duration to this unit.
168			*
169			* <p>For any TimeUnit {@code unit},
170			* {@code unit.convert(Duration.ofNanos(n))}
171			* is equivalent to
172			* {@code unit.convert(n, NANOSECONDS)}, and
173			* {@code unit.convert(Duration.of(n, unit.toChronoUnit()))}
174			* is equivalent to {@code n} (in the absence of overflow).
175			*
176	jsr166	1.65	* <p>This method differs from {@link Duration#toNanos()} in that
177			* it does not throw {@link ArithmeticException} on numeric overflow.
178			*
179	jsr166	1.64	* @param duration the time duration
180			* @return the converted duration in this unit,
181			* or {@code Long.MIN_VALUE} if conversion would negatively overflow,
182			* or {@code Long.MAX_VALUE} if it would positively overflow.
183			* @throws NullPointerException if {@code duration} is null
184			* @see Duration#of(long,TemporalUnit)
185			* @since 11
186			*/
187			public long convert(Duration duration) {
188			long secs = duration.getSeconds();
189			int nano = duration.getNano();
190			if (secs < 0 && nano > 0) {
191			// use representation compatible with integer division
192			secs++;
193	jsr166	1.66	nano -= (int) SECOND_SCALE;
194	jsr166	1.64	}
195			final long s, nanoVal;
196			// Optimize for the common case - NANOSECONDS without overflow
197			if (this == NANOSECONDS)
198			nanoVal = nano;
199			else if ((s = scale) < SECOND_SCALE)
200			nanoVal = nano / s;
201			else if (this == SECONDS)
202			return secs;
203			else
204			return secs / secRatio;
205			long val = secs * secRatio + nanoVal;
206			return ((secs < maxSecs && secs > -maxSecs) \|\|
207			(secs == maxSecs && val > 0) \|\|
208			(secs == -maxSecs && val < 0))
209			? val
210			: (secs > 0) ? Long.MAX_VALUE : Long.MIN_VALUE;
211			}
212
213			/**
214	jsr166	1.41	* Equivalent to
215			* {@link #convert(long, TimeUnit) NANOSECONDS.convert(duration, this)}.
216	dl	1.27	* @param duration the duration
217			* @return the converted duration,
218	jsr166	1.58	* or {@code Long.MIN_VALUE} if conversion would negatively overflow,
219			* or {@code Long.MAX_VALUE} if it would positively overflow.
220	dl	1.27	*/
221	dl	1.32	public long toNanos(long duration) {
222	dl	1.49	long s, m;
223	dl	1.50	if ((s = scale) == NANO_SCALE)
224			return duration;
225			else if (duration > (m = maxNanos))
226			return Long.MAX_VALUE;
227			else if (duration < -m)
228			return Long.MIN_VALUE;
229			else
230			return duration * s;
231	dl	1.32	}
232	jsr166	1.29
233	dl	1.27	/**
234	jsr166	1.41	* Equivalent to
235			* {@link #convert(long, TimeUnit) MICROSECONDS.convert(duration, this)}.
236	dl	1.27	* @param duration the duration
237			* @return the converted duration,
238	jsr166	1.58	* or {@code Long.MIN_VALUE} if conversion would negatively overflow,
239			* or {@code Long.MAX_VALUE} if it would positively overflow.
240	dl	1.27	*/
241	dl	1.32	public long toMicros(long duration) {
242	dl	1.53	long s, m;
243	jsr166	1.64	if ((s = scale) <= MICRO_SCALE)
244			return (s == MICRO_SCALE) ? duration : duration / microRatio;
245	dl	1.53	else if (duration > (m = maxMicros))
246			return Long.MAX_VALUE;
247			else if (duration < -m)
248			return Long.MIN_VALUE;
249			else
250			return duration * microRatio;
251	dl	1.32	}
252	jsr166	1.29
253	dl	1.27	/**
254	jsr166	1.41	* Equivalent to
255			* {@link #convert(long, TimeUnit) MILLISECONDS.convert(duration, this)}.
256	dl	1.27	* @param duration the duration
257			* @return the converted duration,
258	jsr166	1.58	* or {@code Long.MIN_VALUE} if conversion would negatively overflow,
259			* or {@code Long.MAX_VALUE} if it would positively overflow.
260	dl	1.27	*/
261	dl	1.32	public long toMillis(long duration) {
262	dl	1.49	long s, m;
263	jsr166	1.64	if ((s = scale) <= MILLI_SCALE)
264			return (s == MILLI_SCALE) ? duration : duration / milliRatio;
265	dl	1.50	else if (duration > (m = maxMillis))
266			return Long.MAX_VALUE;
267			else if (duration < -m)
268			return Long.MIN_VALUE;
269			else
270	dl	1.52	return duration * milliRatio;
271	dl	1.32	}
272	jsr166	1.29
273	dl	1.27	/**
274	jsr166	1.41	* Equivalent to
275			* {@link #convert(long, TimeUnit) SECONDS.convert(duration, this)}.
276	dl	1.27	* @param duration the duration
277			* @return the converted duration,
278	jsr166	1.58	* or {@code Long.MIN_VALUE} if conversion would negatively overflow,
279			* or {@code Long.MAX_VALUE} if it would positively overflow.
280	dl	1.27	*/
281	dl	1.32	public long toSeconds(long duration) {
282	dl	1.52	long s, m;
283	jsr166	1.64	if ((s = scale) <= SECOND_SCALE)
284			return (s == SECOND_SCALE) ? duration : duration / secRatio;
285	dl	1.52	else if (duration > (m = maxSecs))
286			return Long.MAX_VALUE;
287			else if (duration < -m)
288			return Long.MIN_VALUE;
289			else
290			return duration * secRatio;
291	dl	1.32	}
292	jsr166	1.29
293	dl	1.27	/**
294	jsr166	1.41	* Equivalent to
295			* {@link #convert(long, TimeUnit) MINUTES.convert(duration, this)}.
296	dl	1.27	* @param duration the duration
297			* @return the converted duration,
298	jsr166	1.58	* or {@code Long.MIN_VALUE} if conversion would negatively overflow,
299			* or {@code Long.MAX_VALUE} if it would positively overflow.
300	dl	1.31	* @since 1.6
301	dl	1.27	*/
302	dl	1.32	public long toMinutes(long duration) {
303	dl	1.49	return cvt(duration, MINUTE_SCALE, scale);
304	dl	1.32	}
305	jsr166	1.29
306	dl	1.27	/**
307	jsr166	1.41	* Equivalent to
308			* {@link #convert(long, TimeUnit) HOURS.convert(duration, this)}.
309	dl	1.27	* @param duration the duration
310			* @return the converted duration,
311	jsr166	1.58	* or {@code Long.MIN_VALUE} if conversion would negatively overflow,
312			* or {@code Long.MAX_VALUE} if it would positively overflow.
313	dl	1.31	* @since 1.6
314	dl	1.27	*/
315	dl	1.32	public long toHours(long duration) {
316	dl	1.49	return cvt(duration, HOUR_SCALE, scale);
317	dl	1.32	}
318	jsr166	1.29
319	dl	1.27	/**
320	jsr166	1.41	* Equivalent to
321			* {@link #convert(long, TimeUnit) DAYS.convert(duration, this)}.
322	dl	1.27	* @param duration the duration
323			* @return the converted duration
324	dl	1.31	* @since 1.6
325	dl	1.27	*/
326	dl	1.32	public long toDays(long duration) {
327	dl	1.49	return cvt(duration, DAY_SCALE, scale);
328	dl	1.32	}
329	jsr166	1.29
330	dl	1.27	/**
331			* Utility to compute the excess-nanosecond argument to wait,
332			* sleep, join.
333			* @param d the duration
334			* @param m the number of milliseconds
335			* @return the number of nanoseconds
336			*/
337	dl	1.49	private int excessNanos(long d, long m) {
338			long s;
339	dl	1.50	if ((s = scale) == NANO_SCALE)
340			return (int)(d - (m * MILLI_SCALE));
341			else if (s == MICRO_SCALE)
342			return (int)((d * 1000L) - (m * MILLI_SCALE));
343			else
344			return 0;
345	dl	1.49	}
346	jsr166	1.29
347	dl	1.27	/**
348	jsr166	1.37	* Performs a timed {@link Object#wait(long, int) Object.wait}
349			* using this time unit.
350	dl	1.27	* This is a convenience method that converts timeout arguments
351	jsr166	1.40	* into the form required by the {@code Object.wait} method.
352	dl	1.27	*
353	jsr166	1.60	* <p>For example, you could implement a blocking {@code poll} method
354			* (see {@link BlockingQueue#poll(long, TimeUnit) BlockingQueue.poll})
355	dl	1.27	* using:
356			*
357	jsr166	1.45	* <pre> {@code
358	jsr166	1.62	* public E poll(long timeout, TimeUnit unit)
359	jsr166	1.36	* throws InterruptedException {
360	jsr166	1.62	* synchronized (lock) {
361			* while (isEmpty()) {
362	jsr166	1.63	* unit.timedWait(lock, timeout);
363	jsr166	1.62	* ...
364			* }
365	jsr166	1.36	* }
366			* }}</pre>
367	dl	1.27	*
368			* @param obj the object to wait on
369	dl	1.28	* @param timeout the maximum time to wait. If less than
370			* or equal to zero, do not wait at all.
371	jsr166	1.37	* @throws InterruptedException if interrupted while waiting
372	dl	1.27	*/
373			public void timedWait(Object obj, long timeout)
374	jsr166	1.37	throws InterruptedException {
375	dl	1.27	if (timeout > 0) {
376			long ms = toMillis(timeout);
377			int ns = excessNanos(timeout, ms);
378			obj.wait(ms, ns);
379			}
380			}
381	jsr166	1.29
382	dl	1.27	/**
383	jsr166	1.37	* Performs a timed {@link Thread#join(long, int) Thread.join}
384			* using this time unit.
385	dl	1.27	* This is a convenience method that converts time arguments into the
386	jsr166	1.40	* form required by the {@code Thread.join} method.
387	jsr166	1.37	*
388	dl	1.27	* @param thread the thread to wait for
389	dl	1.28	* @param timeout the maximum time to wait. If less than
390			* or equal to zero, do not wait at all.
391	jsr166	1.37	* @throws InterruptedException if interrupted while waiting
392	dl	1.27	*/
393			public void timedJoin(Thread thread, long timeout)
394	jsr166	1.37	throws InterruptedException {
395	dl	1.27	if (timeout > 0) {
396			long ms = toMillis(timeout);
397			int ns = excessNanos(timeout, ms);
398			thread.join(ms, ns);
399			}
400			}
401	jsr166	1.29
402	dl	1.27	/**
403	jsr166	1.37	* Performs a {@link Thread#sleep(long, int) Thread.sleep} using
404			* this time unit.
405	dl	1.27	* This is a convenience method that converts time arguments into the
406	jsr166	1.40	* form required by the {@code Thread.sleep} method.
407	jsr166	1.37	*
408	dl	1.28	* @param timeout the minimum time to sleep. If less than
409			* or equal to zero, do not sleep at all.
410	jsr166	1.37	* @throws InterruptedException if interrupted while sleeping
411	dl	1.27	*/
412			public void sleep(long timeout) throws InterruptedException {
413			if (timeout > 0) {
414			long ms = toMillis(timeout);
415			int ns = excessNanos(timeout, ms);
416			Thread.sleep(ms, ns);
417			}
418			}
419	jsr166	1.29
420	jsr166	1.48	/**
421			* Converts this {@code TimeUnit} to the equivalent {@code ChronoUnit}.
422			*
423			* @return the converted equivalent ChronoUnit
424			* @since 9
425			*/
426			public ChronoUnit toChronoUnit() {
427			switch (this) {
428			case NANOSECONDS: return ChronoUnit.NANOS;
429			case MICROSECONDS: return ChronoUnit.MICROS;
430			case MILLISECONDS: return ChronoUnit.MILLIS;
431			case SECONDS: return ChronoUnit.SECONDS;
432			case MINUTES: return ChronoUnit.MINUTES;
433			case HOURS: return ChronoUnit.HOURS;
434			case DAYS: return ChronoUnit.DAYS;
435			default: throw new AssertionError();
436			}
437			}
438
439			/**
440			* Converts a {@code ChronoUnit} to the equivalent {@code TimeUnit}.
441			*
442			* @param chronoUnit the ChronoUnit to convert
443			* @return the converted equivalent TimeUnit
444			* @throws IllegalArgumentException if {@code chronoUnit} has no
445			* equivalent TimeUnit
446			* @throws NullPointerException if {@code chronoUnit} is null
447			* @since 9
448			*/
449			public static TimeUnit of(ChronoUnit chronoUnit) {
450			switch (Objects.requireNonNull(chronoUnit, "chronoUnit")) {
451			case NANOS: return TimeUnit.NANOSECONDS;
452			case MICROS: return TimeUnit.MICROSECONDS;
453			case MILLIS: return TimeUnit.MILLISECONDS;
454			case SECONDS: return TimeUnit.SECONDS;
455			case MINUTES: return TimeUnit.MINUTES;
456			case HOURS: return TimeUnit.HOURS;
457			case DAYS: return TimeUnit.DAYS;
458			default:
459			throw new IllegalArgumentException(
460			"No TimeUnit equivalent for " + chronoUnit);
461			}
462			}
463
464	tim	1.1	}