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public enum class: TimeUnit [javadoc | source]
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.
Field Summary
public  TimeUnit NANOSECONDS     
public  TimeUnit MICROSECONDS     
public  TimeUnit MILLISECONDS     
public  TimeUnit SECONDS     
public  TimeUnit MINUTES     
public  TimeUnit HOURS     
public  TimeUnit DAYS     
public static final  long C0     
static final  long C1     
static final  long C2     
static final  long C3     
static final  long C4     
static final  long C5     
static final  long C6     
static final  long MAX     
Method from java.util.concurrent.TimeUnit Summary:
convert,   excessNanos,   sleep,   timedJoin,   timedWait,   toDays,   toHours,   toMicros,   toMillis,   toMinutes,   toNanos,   toSeconds,   x
Method from java.util.concurrent.TimeUnit Detail:
 public 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)

 abstract int excessNanos(long d,
    long m)
    Utility to compute the excess-nanosecond argument to wait, sleep, join.
 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.
 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.
 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);
 public long toDays(long duration) 
    Equivalent to DAYS.convert(duration, this).
 public long toHours(long duration) 
    Equivalent to HOURS.convert(duration, this).
 public long toMicros(long duration) 
    Equivalent to MICROSECONDS.convert(duration, this).
 public long toMillis(long duration) 
    Equivalent to MILLISECONDS.convert(duration, this).
 public long toMinutes(long duration) 
    Equivalent to MINUTES.convert(duration, this).
 public long toNanos(long duration) 
    Equivalent to NANOSECONDS.convert(duration, this).
 public long toSeconds(long duration) 
    Equivalent to SECONDS.convert(duration, this).
 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.