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/OpenJDK 21

Enum Class TimeUnit

java.lang.Object
java.lang.Enum<TimeUnit>
java.util.concurrent.TimeUnit
All Implemented Interfaces:
Serializable, Comparable<TimeUnit>, Constable 
public enum TimeUnit extends Enum<TimeUnit>
A 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 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.

A 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 lock is not available: 

 
 Lock lock = ...;
 if (lock.tryLock(50L, TimeUnit.MILLISECONDS)) ...
while this code will timeout in 50 seconds: 
 
 Lock lock = ...;
 if (lock.tryLock(50L, TimeUnit.SECONDS)) ...
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 TimeUnit.
Since:
1.5

Nested Class Summary

Nested classes/interfaces declared in class java.lang.Enum

Enum.EnumDesc<E extends Enum<E>>

Enum Constant Summary

Enum Constant Description
DAYS
Time unit representing twenty four hours.
HOURS
Time unit representing sixty minutes.
MICROSECONDS
Time unit representing one thousandth of a millisecond.
MILLISECONDS
Time unit representing one thousandth of a second.
MINUTES
Time unit representing sixty seconds.
NANOSECONDS
Time unit representing one thousandth of a microsecond.
SECONDS
Time unit representing one second.

Method Summary

Modifier and Type Method Description
long convert(long sourceDuration, TimeUnit sourceUnit)
Converts the given time duration in the given unit to this unit.
long convert(Duration duration)
Converts the given time duration to this unit.
static TimeUnit of(ChronoUnit chronoUnit)
Converts a ChronoUnit to the equivalent TimeUnit.
void sleep(long timeout)
Performs a Thread.sleep using this time unit.
void timedJoin(Thread thread, long timeout)
Performs a timed Thread.join using this time unit.
void timedWait(Object obj, long timeout)
Performs a timed Object.wait using this time unit.
ChronoUnit toChronoUnit()
Converts this TimeUnit to the equivalent ChronoUnit.
long toDays(long duration)
Equivalent to DAYS.convert(duration, this).
long toHours(long duration)
Equivalent to HOURS.convert(duration, this).
long toMicros(long duration)
Equivalent to MICROSECONDS.convert(duration, this).
long toMillis(long duration)
Equivalent to MILLISECONDS.convert(duration, this).
long toMinutes(long duration)
Equivalent to MINUTES.convert(duration, this).
long toNanos(long duration)
Equivalent to NANOSECONDS.convert(duration, this).
long toSeconds(long duration)
Equivalent to SECONDS.convert(duration, this).
static TimeUnit valueOf(String name)
Returns the enum constant of this class with the specified name.
static TimeUnit[] values()
Returns an array containing the constants of this enum class, in the order they are declared.

Methods declared in class java.lang.Enum

clone, compareTo, describeConstable, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods declared in class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Details

NANOSECONDS

public static final TimeUnit NANOSECONDS
Time unit representing one thousandth of a microsecond.

MICROSECONDS

public static final TimeUnit MICROSECONDS
Time unit representing one thousandth of a millisecond.

MILLISECONDS

public static final TimeUnit MILLISECONDS
Time unit representing one thousandth of a second.

SECONDS

public static final TimeUnit SECONDS
Time unit representing one second.

MINUTES

public static final TimeUnit MINUTES
Time unit representing sixty seconds.
Since:
1.6

HOURS

public static final TimeUnit HOURS
Time unit representing sixty minutes.
Since:
1.6

DAYS

public static final TimeUnit DAYS
Time unit representing twenty four hours.
Since:
1.6

Method Details

values

public static TimeUnit[] values()
Returns an array containing the constants of this enum class, in the order they are declared.
Returns:
an array containing the constants of this enum class, in the order they are declared

valueOf

public static TimeUnit valueOf(String name)
Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (Extraneous whitespace characters are not permitted.)
Parameters:
name - the name of the enum constant to be returned.
Returns:
the enum constant with the specified name
Throws:
IllegalArgumentException - if this enum class has no constant with the specified name
NullPointerException - if the argument is null

convert

public long convert(long sourceDuration, TimeUnit sourceUnit)
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 999 milliseconds to seconds results in 0. Conversions from coarser to finer granularities with arguments that would numerically overflow saturate to Long.MIN_VALUE if negative or Long.MAX_VALUE if positive.

For example, to convert 10 minutes to milliseconds, use: TimeUnit.MILLISECONDS.convert(10L, TimeUnit.MINUTES)

Parameters:
sourceDuration - the time duration in the given sourceUnit
sourceUnit - the unit of the sourceDuration argument
Returns:
the converted duration in this unit, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.

convert

public long convert(Duration duration)
Converts the given time duration to this unit.

For any TimeUnit unit, unit.convert(Duration.ofNanos(n)) is equivalent to unit.convert(n, NANOSECONDS), and unit.convert(Duration.of(n, unit.toChronoUnit())) is equivalent to n (in the absence of overflow).

API Note:
This method differs from Duration.toNanos() in that it does not throw ArithmeticException on numeric overflow.
Parameters:
duration - the time duration
Returns:
the converted duration in this unit, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
Throws:
NullPointerException - if duration is null
Since:
11
See Also:

toNanos

public long toNanos(long duration)
Equivalent to NANOSECONDS.convert(duration, this).
Parameters:
duration - the duration
Returns:
the converted duration, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.

toMicros

public long toMicros(long duration)
Equivalent to MICROSECONDS.convert(duration, this).
Parameters:
duration - the duration
Returns:
the converted duration, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.

toMillis

public long toMillis(long duration)
Equivalent to MILLISECONDS.convert(duration, this).
Parameters:
duration - the duration
Returns:
the converted duration, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.

toSeconds

public long toSeconds(long duration)
Equivalent to SECONDS.convert(duration, this).
Parameters:
duration - the duration
Returns:
the converted duration, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.

toMinutes

public long toMinutes(long duration)
Equivalent to MINUTES.convert(duration, this).
Parameters:
duration - the duration
Returns:
the converted duration, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
Since:
1.6

toHours

public long toHours(long duration)
Equivalent to HOURS.convert(duration, this).
Parameters:
duration - the duration
Returns:
the converted duration, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
Since:
1.6

toDays

public long toDays(long duration)
Equivalent to DAYS.convert(duration, this).
Parameters:
duration - the duration
Returns:
the converted duration
Since:
1.6

timedWait

public void timedWait(Object obj, long timeout) throws InterruptedException
Performs a timed Object.wait using this time unit. This is a convenience method that converts timeout arguments into the form required by the Object.wait method.

For example, you could implement a blocking poll method (see BlockingQueue.poll) using: 

 
 public E poll(long timeout, TimeUnit unit)
     throws InterruptedException {
   synchronized (lock) {
     while (isEmpty()) {
       unit.timedWait(lock, timeout);
       ...
     }
   }
 }
Parameters:
obj - the object to wait on
timeout - the maximum time to wait. If less than or equal to zero, do not wait at all.
Throws:
InterruptedException - if interrupted while waiting

timedJoin

public void timedJoin(Thread thread, long timeout) throws InterruptedException
Performs a timed Thread.join using this time unit. This is a convenience method that converts time arguments into the form required by the Thread.join method.
Parameters:
thread - the thread to wait for
timeout - the maximum time to wait. If less than or equal to zero, do not wait at all.
Throws:
InterruptedException - if interrupted while waiting

sleep

public void sleep(long timeout) throws InterruptedException
Performs a Thread.sleep using this time unit. This is a convenience method that converts time arguments into the form required by the Thread.sleep method.
Parameters:
timeout - the minimum time to sleep. If less than or equal to zero, do not sleep at all.
Throws:
InterruptedException - if interrupted while sleeping

toChronoUnit

public ChronoUnit toChronoUnit()
Converts this TimeUnit to the equivalent ChronoUnit.
Returns:
the converted equivalent ChronoUnit
Since:
9

of

public static TimeUnit of(ChronoUnit chronoUnit)
Converts a ChronoUnit to the equivalent TimeUnit.
Parameters:
chronoUnit - the ChronoUnit to convert
Returns:
the converted equivalent TimeUnit
Throws:
IllegalArgumentException - if chronoUnit has no equivalent TimeUnit
NullPointerException - if chronoUnit is null
Since:
9

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Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/util/concurrent/TimeUnit.html