org.compass.core.util.backport.java.util.concurrent
Class TimeUnit

java.lang.Object
  org.compass.core.util.backport.java.util.concurrent.TimeUnit

All Implemented Interfaces:

Serializable

public abstract class TimeUnit
extends Object
implements Serializable

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

Author:

Doug Lea

See Also:

Serialized Form

Field Summary

(package private) static long	C0
(package private) static long	C1
(package private) static long	C2
(package private) static long	C3
(package private) static long	C4
(package private) static long	C5
(package private) static long	C6
static TimeUnit	DAYS
static TimeUnit	HOURS
(package private) static long	MAX
static TimeUnit	MICROSECONDS
static TimeUnit	MILLISECONDS
static TimeUnit	MINUTES
static TimeUnit	NANOSECONDS
static TimeUnit	SECONDS

Constructor Summary

TimeUnit(int index, String name)
Internal constructor

Method Summary

abstract long	convert(long sourceDuration, TimeUnit sourceUnit) Convert the given time duration in the given unit to this unit.
(package private) abstract int	excessNanos(long d, long m) Utility to compute the excess-nanosecond argument to wait, sleep, join.
void	sleep(long timeout) Performs a Thread.sleep using this 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.
abstract long	toDays(long duration) Equivalent to DAYS.convert(duration, this).
abstract long	toHours(long duration) Equivalent to HOURS.convert(duration, this).
abstract long	toMicros(long duration) Equivalent to MICROSECONDS.convert(duration, this).
abstract long	toMillis(long duration) Equivalent to MILLISECONDS.convert(duration, this).
abstract long	toMinutes(long duration) Equivalent to MINUTES.convert(duration, this).
abstract long	toNanos(long duration) Equivalent to NANOSECONDS.convert(duration, this).
abstract long	toSeconds(long duration) Equivalent to SECONDS.convert(duration, this).
String	toString()
static TimeUnit[]	values()
(package private) static long	x(long d, long m, long over) Scale d by m, checking for overflow.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

NANOSECONDS

public static final TimeUnit NANOSECONDS

MICROSECONDS

public static final TimeUnit MICROSECONDS

MILLISECONDS

public static final TimeUnit MILLISECONDS

SECONDS

public static final TimeUnit SECONDS

MINUTES

public static final TimeUnit MINUTES

HOURS

public static final TimeUnit HOURS

DAYS

public static final TimeUnit DAYS

C0

static final long C0

See Also:

Constant Field Values

C1

static final long C1

See Also:

Constant Field Values

C2

static final long C2

See Also:

Constant Field Values

C3

static final long C3

See Also:

Constant Field Values

C4

static final long C4

See Also:

Constant Field Values

C5

static final long C5

See Also:

Constant Field Values

C6

static final long C6

See Also:

Constant Field Values

MAX

static final long MAX

See Also:

Constant Field Values

Constructor Detail

TimeUnit

TimeUnit(int index,
         String name)

Internal constructor

Method Detail

values

public static TimeUnit[] values()

x

static long x(long d,
              long m,
              long over)

Scale d by m, checking for overflow. This has a short name to make above code more readable.

convert

public abstract long convert(long sourceDuration,
                             TimeUnit sourceUnit)

Convert 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.

toNanos

public abstract 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.

See Also:

convert(long, org.compass.core.util.backport.java.util.concurrent.TimeUnit)

toMicros

public abstract 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.

See Also:

convert(long, org.compass.core.util.backport.java.util.concurrent.TimeUnit)

toMillis

public abstract 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.

See Also:

convert(long, org.compass.core.util.backport.java.util.concurrent.TimeUnit)

toSeconds

public abstract 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.

See Also:

convert(long, org.compass.core.util.backport.java.util.concurrent.TimeUnit)

toMinutes

public abstract 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

See Also:

convert(long, org.compass.core.util.backport.java.util.concurrent.TimeUnit)

toHours

public abstract 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

See Also:

convert(long, org.compass.core.util.backport.java.util.concurrent.TimeUnit)

toDays

public abstract long toDays(long duration)

Equivalent to DAYS.convert(duration, this).

Parameters:

duration - the duration

Returns:

the converted duration

Since:

1.6

See Also:

convert(long, org.compass.core.util.backport.java.util.concurrent.TimeUnit)

excessNanos

abstract int excessNanos(long d,
                         long m)

Utility to compute the excess-nanosecond argument to wait, sleep, join.

Parameters:

d - the duration

m - the number of milliseconds

Returns:

the number of nanoseconds

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 synchronized  Object poll(long timeout, TimeUnit unit) throws InterruptedException {
    while (empty) {
      unit.timedWait(this, 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.

See Also:

Object.wait(long, int)

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.

See Also:

Thread.join(long, int)

sleep

public void sleep(long timeout)
           throws InterruptedException

Performs a Thread.sleep using this unit. This is a convenience method that converts time arguments into the form required by the Thread.sleep method.

Parameters:

timeout - the maximum time to sleep. If less than or equal to zero, do not sleep at all.

Throws:

InterruptedException - if interrupted while sleeping.

See Also:

Thread.sleep(long)

toString

public String toString()

Overrides:

toString in class Object