jaroslav@633: /*
jaroslav@633:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jaroslav@633:  *
jaroslav@633:  * This code is free software; you can redistribute it and/or modify it
jaroslav@633:  * under the terms of the GNU General Public License version 2 only, as
jaroslav@633:  * published by the Free Software Foundation.  Oracle designates this
jaroslav@633:  * particular file as subject to the "Classpath" exception as provided
jaroslav@633:  * by Oracle in the LICENSE file that accompanied this code.
jaroslav@633:  *
jaroslav@633:  * This code is distributed in the hope that it will be useful, but WITHOUT
jaroslav@633:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jaroslav@633:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
jaroslav@633:  * version 2 for more details (a copy is included in the LICENSE file that
jaroslav@633:  * accompanied this code).
jaroslav@633:  *
jaroslav@633:  * You should have received a copy of the GNU General Public License version
jaroslav@633:  * 2 along with this work; if not, write to the Free Software Foundation,
jaroslav@633:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jaroslav@633:  *
jaroslav@633:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
jaroslav@633:  * or visit www.oracle.com if you need additional information or have any
jaroslav@633:  * questions.
jaroslav@633:  */
jaroslav@633: 
jaroslav@633: /*
jaroslav@633:  * This file is available under and governed by the GNU General Public
jaroslav@633:  * License version 2 only, as published by the Free Software Foundation.
jaroslav@633:  * However, the following notice accompanied the original version of this
jaroslav@633:  * file:
jaroslav@633:  *
jaroslav@633:  * Written by Doug Lea with assistance from members of JCP JSR-166
jaroslav@633:  * Expert Group and released to the public domain, as explained at
jaroslav@633:  * http://creativecommons.org/publicdomain/zero/1.0/
jaroslav@633:  */
jaroslav@633: 
jaroslav@633: package java.util.concurrent;
jaroslav@633: 
jaroslav@633: /**
jaroslav@633:  * A <tt>TimeUnit</tt> represents time durations at a given unit of
jaroslav@633:  * granularity and provides utility methods to convert across units,
jaroslav@633:  * and to perform timing and delay operations in these units.  A
jaroslav@633:  * <tt>TimeUnit</tt> does not maintain time information, but only
jaroslav@633:  * helps organize and use time representations that may be maintained
jaroslav@633:  * separately across various contexts.  A nanosecond is defined as one
jaroslav@633:  * thousandth of a microsecond, a microsecond as one thousandth of a
jaroslav@633:  * millisecond, a millisecond as one thousandth of a second, a minute
jaroslav@633:  * as sixty seconds, an hour as sixty minutes, and a day as twenty four
jaroslav@633:  * hours.
jaroslav@633:  *
jaroslav@633:  * <p>A <tt>TimeUnit</tt> is mainly used to inform time-based methods
jaroslav@633:  * how a given timing parameter should be interpreted. For example,
jaroslav@633:  * the following code will timeout in 50 milliseconds if the {@link
jaroslav@633:  * java.util.concurrent.locks.Lock lock} is not available:
jaroslav@633:  *
jaroslav@633:  * <pre>  Lock lock = ...;
jaroslav@633:  *  if (lock.tryLock(50L, TimeUnit.MILLISECONDS)) ...
jaroslav@633:  * </pre>
jaroslav@633:  * while this code will timeout in 50 seconds:
jaroslav@633:  * <pre>
jaroslav@633:  *  Lock lock = ...;
jaroslav@633:  *  if (lock.tryLock(50L, TimeUnit.SECONDS)) ...
jaroslav@633:  * </pre>
jaroslav@633:  *
jaroslav@633:  * Note however, that there is no guarantee that a particular timeout
jaroslav@633:  * implementation will be able to notice the passage of time at the
jaroslav@633:  * same granularity as the given <tt>TimeUnit</tt>.
jaroslav@633:  *
jaroslav@633:  * @since 1.5
jaroslav@633:  * @author Doug Lea
jaroslav@633:  */
jaroslav@633: public enum TimeUnit {
jaroslav@633:     NANOSECONDS {
jaroslav@633:         public long toNanos(long d)   { return d; }
jaroslav@633:         public long toMicros(long d)  { return d/(C1/C0); }
jaroslav@633:         public long toMillis(long d)  { return d/(C2/C0); }
jaroslav@633:         public long toSeconds(long d) { return d/(C3/C0); }
jaroslav@633:         public long toMinutes(long d) { return d/(C4/C0); }
jaroslav@633:         public long toHours(long d)   { return d/(C5/C0); }
jaroslav@633:         public long toDays(long d)    { return d/(C6/C0); }
jaroslav@633:         public long convert(long d, TimeUnit u) { return u.toNanos(d); }
jaroslav@633:         int excessNanos(long d, long m) { return (int)(d - (m*C2)); }
jaroslav@633:     },
jaroslav@633:     MICROSECONDS {
jaroslav@633:         public long toNanos(long d)   { return x(d, C1/C0, MAX/(C1/C0)); }
jaroslav@633:         public long toMicros(long d)  { return d; }
jaroslav@633:         public long toMillis(long d)  { return d/(C2/C1); }
jaroslav@633:         public long toSeconds(long d) { return d/(C3/C1); }
jaroslav@633:         public long toMinutes(long d) { return d/(C4/C1); }
jaroslav@633:         public long toHours(long d)   { return d/(C5/C1); }
jaroslav@633:         public long toDays(long d)    { return d/(C6/C1); }
jaroslav@633:         public long convert(long d, TimeUnit u) { return u.toMicros(d); }
jaroslav@633:         int excessNanos(long d, long m) { return (int)((d*C1) - (m*C2)); }
jaroslav@633:     },
jaroslav@633:     MILLISECONDS {
jaroslav@633:         public long toNanos(long d)   { return x(d, C2/C0, MAX/(C2/C0)); }
jaroslav@633:         public long toMicros(long d)  { return x(d, C2/C1, MAX/(C2/C1)); }
jaroslav@633:         public long toMillis(long d)  { return d; }
jaroslav@633:         public long toSeconds(long d) { return d/(C3/C2); }
jaroslav@633:         public long toMinutes(long d) { return d/(C4/C2); }
jaroslav@633:         public long toHours(long d)   { return d/(C5/C2); }
jaroslav@633:         public long toDays(long d)    { return d/(C6/C2); }
jaroslav@633:         public long convert(long d, TimeUnit u) { return u.toMillis(d); }
jaroslav@633:         int excessNanos(long d, long m) { return 0; }
jaroslav@633:     },
jaroslav@633:     SECONDS {
jaroslav@633:         public long toNanos(long d)   { return x(d, C3/C0, MAX/(C3/C0)); }
jaroslav@633:         public long toMicros(long d)  { return x(d, C3/C1, MAX/(C3/C1)); }
jaroslav@633:         public long toMillis(long d)  { return x(d, C3/C2, MAX/(C3/C2)); }
jaroslav@633:         public long toSeconds(long d) { return d; }
jaroslav@633:         public long toMinutes(long d) { return d/(C4/C3); }
jaroslav@633:         public long toHours(long d)   { return d/(C5/C3); }
jaroslav@633:         public long toDays(long d)    { return d/(C6/C3); }
jaroslav@633:         public long convert(long d, TimeUnit u) { return u.toSeconds(d); }
jaroslav@633:         int excessNanos(long d, long m) { return 0; }
jaroslav@633:     },
jaroslav@633:     MINUTES {
jaroslav@633:         public long toNanos(long d)   { return x(d, C4/C0, MAX/(C4/C0)); }
jaroslav@633:         public long toMicros(long d)  { return x(d, C4/C1, MAX/(C4/C1)); }
jaroslav@633:         public long toMillis(long d)  { return x(d, C4/C2, MAX/(C4/C2)); }
jaroslav@633:         public long toSeconds(long d) { return x(d, C4/C3, MAX/(C4/C3)); }
jaroslav@633:         public long toMinutes(long d) { return d; }
jaroslav@633:         public long toHours(long d)   { return d/(C5/C4); }
jaroslav@633:         public long toDays(long d)    { return d/(C6/C4); }
jaroslav@633:         public long convert(long d, TimeUnit u) { return u.toMinutes(d); }
jaroslav@633:         int excessNanos(long d, long m) { return 0; }
jaroslav@633:     },
jaroslav@633:     HOURS {
jaroslav@633:         public long toNanos(long d)   { return x(d, C5/C0, MAX/(C5/C0)); }
jaroslav@633:         public long toMicros(long d)  { return x(d, C5/C1, MAX/(C5/C1)); }
jaroslav@633:         public long toMillis(long d)  { return x(d, C5/C2, MAX/(C5/C2)); }
jaroslav@633:         public long toSeconds(long d) { return x(d, C5/C3, MAX/(C5/C3)); }
jaroslav@633:         public long toMinutes(long d) { return x(d, C5/C4, MAX/(C5/C4)); }
jaroslav@633:         public long toHours(long d)   { return d; }
jaroslav@633:         public long toDays(long d)    { return d/(C6/C5); }
jaroslav@633:         public long convert(long d, TimeUnit u) { return u.toHours(d); }
jaroslav@633:         int excessNanos(long d, long m) { return 0; }
jaroslav@633:     },
jaroslav@633:     DAYS {
jaroslav@633:         public long toNanos(long d)   { return x(d, C6/C0, MAX/(C6/C0)); }
jaroslav@633:         public long toMicros(long d)  { return x(d, C6/C1, MAX/(C6/C1)); }
jaroslav@633:         public long toMillis(long d)  { return x(d, C6/C2, MAX/(C6/C2)); }
jaroslav@633:         public long toSeconds(long d) { return x(d, C6/C3, MAX/(C6/C3)); }
jaroslav@633:         public long toMinutes(long d) { return x(d, C6/C4, MAX/(C6/C4)); }
jaroslav@633:         public long toHours(long d)   { return x(d, C6/C5, MAX/(C6/C5)); }
jaroslav@633:         public long toDays(long d)    { return d; }
jaroslav@633:         public long convert(long d, TimeUnit u) { return u.toDays(d); }
jaroslav@633:         int excessNanos(long d, long m) { return 0; }
jaroslav@633:     };
jaroslav@633: 
jaroslav@633:     // Handy constants for conversion methods
jaroslav@633:     static final long C0 = 1L;
jaroslav@633:     static final long C1 = C0 * 1000L;
jaroslav@633:     static final long C2 = C1 * 1000L;
jaroslav@633:     static final long C3 = C2 * 1000L;
jaroslav@633:     static final long C4 = C3 * 60L;
jaroslav@633:     static final long C5 = C4 * 60L;
jaroslav@633:     static final long C6 = C5 * 24L;
jaroslav@633: 
jaroslav@633:     static final long MAX = Long.MAX_VALUE;
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Scale d by m, checking for overflow.
jaroslav@633:      * This has a short name to make above code more readable.
jaroslav@633:      */
jaroslav@633:     static long x(long d, long m, long over) {
jaroslav@633:         if (d >  over) return Long.MAX_VALUE;
jaroslav@633:         if (d < -over) return Long.MIN_VALUE;
jaroslav@633:         return d * m;
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     // To maintain full signature compatibility with 1.5, and to improve the
jaroslav@633:     // clarity of the generated javadoc (see 6287639: Abstract methods in
jaroslav@633:     // enum classes should not be listed as abstract), method convert
jaroslav@633:     // etc. are not declared abstract but otherwise act as abstract methods.
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Convert the given time duration in the given unit to this
jaroslav@633:      * unit.  Conversions from finer to coarser granularities
jaroslav@633:      * truncate, so lose precision. For example converting
jaroslav@633:      * <tt>999</tt> milliseconds to seconds results in
jaroslav@633:      * <tt>0</tt>. Conversions from coarser to finer granularities
jaroslav@633:      * with arguments that would numerically overflow saturate to
jaroslav@633:      * <tt>Long.MIN_VALUE</tt> if negative or <tt>Long.MAX_VALUE</tt>
jaroslav@633:      * if positive.
jaroslav@633:      *
jaroslav@633:      * <p>For example, to convert 10 minutes to milliseconds, use:
jaroslav@633:      * <tt>TimeUnit.MILLISECONDS.convert(10L, TimeUnit.MINUTES)</tt>
jaroslav@633:      *
jaroslav@633:      * @param sourceDuration the time duration in the given <tt>sourceUnit</tt>
jaroslav@633:      * @param sourceUnit the unit of the <tt>sourceDuration</tt> argument
jaroslav@633:      * @return the converted duration in this unit,
jaroslav@633:      * or <tt>Long.MIN_VALUE</tt> if conversion would negatively
jaroslav@633:      * overflow, or <tt>Long.MAX_VALUE</tt> if it would positively overflow.
jaroslav@633:      */
jaroslav@633:     public long convert(long sourceDuration, TimeUnit sourceUnit) {
jaroslav@633:         throw new AbstractMethodError();
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Equivalent to <tt>NANOSECONDS.convert(duration, this)</tt>.
jaroslav@633:      * @param duration the duration
jaroslav@633:      * @return the converted duration,
jaroslav@633:      * or <tt>Long.MIN_VALUE</tt> if conversion would negatively
jaroslav@633:      * overflow, or <tt>Long.MAX_VALUE</tt> if it would positively overflow.
jaroslav@633:      * @see #convert
jaroslav@633:      */
jaroslav@633:     public long toNanos(long duration) {
jaroslav@633:         throw new AbstractMethodError();
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Equivalent to <tt>MICROSECONDS.convert(duration, this)</tt>.
jaroslav@633:      * @param duration the duration
jaroslav@633:      * @return the converted duration,
jaroslav@633:      * or <tt>Long.MIN_VALUE</tt> if conversion would negatively
jaroslav@633:      * overflow, or <tt>Long.MAX_VALUE</tt> if it would positively overflow.
jaroslav@633:      * @see #convert
jaroslav@633:      */
jaroslav@633:     public long toMicros(long duration) {
jaroslav@633:         throw new AbstractMethodError();
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Equivalent to <tt>MILLISECONDS.convert(duration, this)</tt>.
jaroslav@633:      * @param duration the duration
jaroslav@633:      * @return the converted duration,
jaroslav@633:      * or <tt>Long.MIN_VALUE</tt> if conversion would negatively
jaroslav@633:      * overflow, or <tt>Long.MAX_VALUE</tt> if it would positively overflow.
jaroslav@633:      * @see #convert
jaroslav@633:      */
jaroslav@633:     public long toMillis(long duration) {
jaroslav@633:         throw new AbstractMethodError();
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Equivalent to <tt>SECONDS.convert(duration, this)</tt>.
jaroslav@633:      * @param duration the duration
jaroslav@633:      * @return the converted duration,
jaroslav@633:      * or <tt>Long.MIN_VALUE</tt> if conversion would negatively
jaroslav@633:      * overflow, or <tt>Long.MAX_VALUE</tt> if it would positively overflow.
jaroslav@633:      * @see #convert
jaroslav@633:      */
jaroslav@633:     public long toSeconds(long duration) {
jaroslav@633:         throw new AbstractMethodError();
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Equivalent to <tt>MINUTES.convert(duration, this)</tt>.
jaroslav@633:      * @param duration the duration
jaroslav@633:      * @return the converted duration,
jaroslav@633:      * or <tt>Long.MIN_VALUE</tt> if conversion would negatively
jaroslav@633:      * overflow, or <tt>Long.MAX_VALUE</tt> if it would positively overflow.
jaroslav@633:      * @see #convert
jaroslav@633:      * @since 1.6
jaroslav@633:      */
jaroslav@633:     public long toMinutes(long duration) {
jaroslav@633:         throw new AbstractMethodError();
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Equivalent to <tt>HOURS.convert(duration, this)</tt>.
jaroslav@633:      * @param duration the duration
jaroslav@633:      * @return the converted duration,
jaroslav@633:      * or <tt>Long.MIN_VALUE</tt> if conversion would negatively
jaroslav@633:      * overflow, or <tt>Long.MAX_VALUE</tt> if it would positively overflow.
jaroslav@633:      * @see #convert
jaroslav@633:      * @since 1.6
jaroslav@633:      */
jaroslav@633:     public long toHours(long duration) {
jaroslav@633:         throw new AbstractMethodError();
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Equivalent to <tt>DAYS.convert(duration, this)</tt>.
jaroslav@633:      * @param duration the duration
jaroslav@633:      * @return the converted duration
jaroslav@633:      * @see #convert
jaroslav@633:      * @since 1.6
jaroslav@633:      */
jaroslav@633:     public long toDays(long duration) {
jaroslav@633:         throw new AbstractMethodError();
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Utility to compute the excess-nanosecond argument to wait,
jaroslav@633:      * sleep, join.
jaroslav@633:      * @param d the duration
jaroslav@633:      * @param m the number of milliseconds
jaroslav@633:      * @return the number of nanoseconds
jaroslav@633:      */
jaroslav@633:     abstract int excessNanos(long d, long m);
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Performs a timed {@link Object#wait(long, int) Object.wait}
jaroslav@633:      * using this time unit.
jaroslav@633:      * This is a convenience method that converts timeout arguments
jaroslav@633:      * into the form required by the <tt>Object.wait</tt> method.
jaroslav@633:      *
jaroslav@633:      * <p>For example, you could implement a blocking <tt>poll</tt>
jaroslav@633:      * method (see {@link BlockingQueue#poll BlockingQueue.poll})
jaroslav@633:      * using:
jaroslav@633:      *
jaroslav@633:      *  <pre> {@code
jaroslav@633:      * public synchronized Object poll(long timeout, TimeUnit unit)
jaroslav@633:      *     throws InterruptedException {
jaroslav@633:      *   while (empty) {
jaroslav@633:      *     unit.timedWait(this, timeout);
jaroslav@633:      *     ...
jaroslav@633:      *   }
jaroslav@633:      * }}</pre>
jaroslav@633:      *
jaroslav@633:      * @param obj the object to wait on
jaroslav@633:      * @param timeout the maximum time to wait. If less than
jaroslav@633:      * or equal to zero, do not wait at all.
jaroslav@633:      * @throws InterruptedException if interrupted while waiting
jaroslav@633:      */
jaroslav@633:     public void timedWait(Object obj, long timeout)
jaroslav@633:             throws InterruptedException {
jaroslav@633:         if (timeout > 0) {
jaroslav@633:             long ms = toMillis(timeout);
jaroslav@633:             int ns = excessNanos(timeout, ms);
jaroslav@633:             obj.wait(ms, ns);
jaroslav@633:         }
jaroslav@633:     }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Performs a timed {@link Thread#join(long, int) Thread.join}
jaroslav@633:      * using this time unit.
jaroslav@633:      * This is a convenience method that converts time arguments into the
jaroslav@633:      * form required by the <tt>Thread.join</tt> method.
jaroslav@633:      *
jaroslav@633:      * @param thread the thread to wait for
jaroslav@633:      * @param timeout the maximum time to wait. If less than
jaroslav@633:      * or equal to zero, do not wait at all.
jaroslav@633:      * @throws InterruptedException if interrupted while waiting
jaroslav@633:      */
jaroslav@635: //    public void timedJoin(Thread thread, long timeout)
jaroslav@635: //            throws InterruptedException {
jaroslav@635: //        if (timeout > 0) {
jaroslav@635: //            long ms = toMillis(timeout);
jaroslav@635: //            int ns = excessNanos(timeout, ms);
jaroslav@635: //            thread.join(ms, ns);
jaroslav@635: //        }
jaroslav@635: //    }
jaroslav@633: 
jaroslav@633:     /**
jaroslav@633:      * Performs a {@link Thread#sleep(long, int) Thread.sleep} using
jaroslav@633:      * this time unit.
jaroslav@633:      * This is a convenience method that converts time arguments into the
jaroslav@633:      * form required by the <tt>Thread.sleep</tt> method.
jaroslav@633:      *
jaroslav@633:      * @param timeout the minimum time to sleep. If less than
jaroslav@633:      * or equal to zero, do not sleep at all.
jaroslav@633:      * @throws InterruptedException if interrupted while sleeping
jaroslav@633:      */
jaroslav@633:     public void sleep(long timeout) throws InterruptedException {
jaroslav@633:         if (timeout > 0) {
jaroslav@633:             long ms = toMillis(timeout);
jaroslav@633:             int ns = excessNanos(timeout, ms);
jaroslav@635:             Object o = new Object();
jaroslav@635:             synchronized (o) {
jaroslav@635:                 o.wait(ms, ns);
jaroslav@635:             }
jaroslav@633:         }
jaroslav@633:     }
jaroslav@633: 
jaroslav@633: }