scala.concurrent.duration (original) (raw)
This class stores a deadline, as obtained via Deadline.now or the duration DSL:
This class stores a deadline, as obtained via Deadline.now or the duration DSL:
import scala.concurrent.duration._
3.seconds.fromNow
Its main purpose is to manage repeated attempts to achieve something (like awaiting a condition) by offering the methods hasTimeLeft and timeLeft. All durations are measured according to System.nanoTime; this does not take into account changes to the system clock (such as leap seconds).
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This class is not meant as a general purpose representation of time, it is optimized for the needs of scala.concurrent.
Utility for working with java.util.concurrent.TimeUnit durations.
This class is not meant as a general purpose representation of time, it is optimized for the needs of scala.concurrent.
Basic Usage
Examples:
import scala.concurrent.duration._
val duration = Duration(100, MILLISECONDS)
val duration = Duration(100, "millis")
duration.toNanos
duration < 1.second
duration <= Duration.Inf
Invoking inexpressible conversions (like calling toSeconds on an infinite duration) will throw an IllegalArgumentException.
Implicits are also provided for Int, Long and Double. Example usage:
import scala.concurrent.duration._
val duration = 100.millis
The DSL provided by the implicit conversions always allows construction of finite durations, even for infinite Double inputs; use Duration.Inf instead.
Extractors, parsing and arithmetic are also included:
val d = Duration("1.2 µs")
val Duration(length, unit) = 5 millis
val d2 = d * 2.5
val d3 = d2 + 1.millisecond
Handling of Time Units
Calculations performed on finite durations always retain the more precise unit of either operand, no matter whether a coarser unit would be able to exactly express the same duration. This means that Duration can be used as a lossless container for a (length, unit) pair if it is constructed using the corresponding methods and no arithmetic is performed on it; adding/subtracting durations should in that case be done with care.
Correspondence to Double Semantics
The semantics of arithmetic operations on Duration are two-fold:
- exact addition/subtraction with nanosecond resolution for finite durations, independent of the summands' magnitude - isomorphic to java.lang.Double when it comes to infinite or undefined values
The conversion between Duration and Double is done using Duration.toUnit (with unit NANOSECONDS) and Duration.fromNanos(Double)
Ordering
The default ordering is consistent with the ordering of Double numbers, which means that Undefined is considered greater than all other durations, including Duration.Inf.
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Known subtypes
This object just holds some cogs which make the DSL machine work, not for direct consumption.
This object just holds some cogs which make the DSL machine work, not for direct consumption.
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Companion
Source
Supertypes
Self type
This class represents a finite duration.
This class represents a finite duration. Its addition and subtraction operators are overloaded to retain this guarantee statically. The range of this class is limited to +-(2^63-1)`ns, which is roughly 292 years. `
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This object can be used as closing token for declaring a deadline at some future point in time:
This object can be used as closing token for declaring a deadline at some future point in time:
import scala.concurrent.duration._
val deadline = 3 seconds fromNow
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This object can be used as closing token if you prefer dot-less style but do not want to enable language.postfixOps:
This object can be used as closing token if you prefer dot-less style but do not want to enable language.postfixOps:
import scala.concurrent.duration._
val duration = 2 seconds span
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Source
Supertypes
Self type