org.apache.openjpa.lib.util.concurrent
Class TimeUnit

java.lang.Object
  extended by org.apache.openjpa.lib.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
static TimeUnit DAYS
           
static TimeUnit HOURS
           
static TimeUnit MICROSECONDS
           
static TimeUnit MILLISECONDS
           
static TimeUnit MINUTES
           
static TimeUnit NANOSECONDS
           
static TimeUnit SECONDS
           
 
Method Summary
abstract  long convert(long sourceDuration, TimeUnit sourceUnit)
          Convert the given time duration in the given unit to this unit.
 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()
           
 
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
Method Detail

values

public static TimeUnit[] values()

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.apache.openjpa.lib.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.apache.openjpa.lib.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.apache.openjpa.lib.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.apache.openjpa.lib.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.apache.openjpa.lib.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.apache.openjpa.lib.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.apache.openjpa.lib.util.concurrent.TimeUnit)

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


Copyright © 2006 Apache Software Foundation. All Rights Reserved.