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 Enum

Enum.EnumDesc<E>

Modifier and Type	Class	Description
`static final class`	`Enum.EnumDesc<E extends Enum<E>>`	A nominal descriptor for an `enum` constant.

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 Enum

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

Modifier and Type	Method	Description
`protected final Object`	`clone()`	Throws CloneNotSupportedException.
`final int`	`compareTo(TimeUnit o)`	Compares this enum with the specified object for order.
`final Optional<Enum.EnumDesc<TimeUnit>>`	`describeConstable()`	Returns an enum descriptor `EnumDesc` for this instance, if one can be constructed, or an empty `Optional` if one cannot be.
`final boolean`	`equals(Object other)`	Returns true if the specified object is equal to this enum constant.
`protected final void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization has been deprecated for removal.
`final Class<TimeUnit>`	`getDeclaringClass()`	Returns the Class object corresponding to this enum constant's enum type.
`final int`	`hashCode()`	Returns a hash code for this enum constant.
`final String`	`name()`	Returns the name of this enum constant, exactly as declared in its enum declaration.
`final int`	`ordinal()`	Returns the ordinal of this enumeration constant (its position in its enum declaration, where the initial constant is assigned an ordinal of zero).
`String`	`toString()`	Returns the name of this enum constant, as contained in the declaration.
`static <T extends Enum<T>> T`	`valueOf(Class<T> enumClass, String name)`	Returns the enum constant of the specified enum class with the specified name.

Methods declared in class Object

getClass, notify, notifyAll, wait, wait, wait

Modifier and Type	Method	Description
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

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:

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:: IllegalMonitorStateException - if the current thread is not the owner of the object's monitor.; 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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