Packages

  • package root

    This is the documentation for the Scala standard library.

    This is the documentation for the Scala standard library.

    Package structure

    The scala package contains core types like Int, Float, Array or Option which are accessible in all Scala compilation units without explicit qualification or imports.

    Notable packages include:

    Other packages exist. See the complete list on the right.

    Additional parts of the standard library are shipped as separate libraries. These include:

    • scala.reflect - Scala's reflection API (scala-reflect.jar)
    • scala.xml - XML parsing, manipulation, and serialization (scala-xml.jar)
    • scala.swing - A convenient wrapper around Java's GUI framework called Swing (scala-swing.jar)
    • scala.util.parsing - Parser combinators (scala-parser-combinators.jar)

    Automatic imports

    Identifiers in the scala package and the scala.Predef object are always in scope by default.

    Some of these identifiers are type aliases provided as shortcuts to commonly used classes. For example, List is an alias for scala.collection.immutable.List.

    Other aliases refer to classes provided by the underlying platform. For example, on the JVM, String is an alias for java.lang.String.

    Definition Classes
    root
  • package scala

    Core Scala types.

    Core Scala types. They are always available without an explicit import.

    Definition Classes
    root
  • package concurrent

    This package object contains primitives for concurrent and parallel programming.

    This package object contains primitives for concurrent and parallel programming.

    Guide

    A more detailed guide to Futures and Promises, including discussion and examples can be found at http://docs.scala-lang.org/overviews/core/futures.html.

    Common Imports

    When working with Futures, you will often find that importing the whole concurrent package is convenient:

    import scala.concurrent._

    When using things like Futures, it is often required to have an implicit ExecutionContext in scope. The general advice for these implicits are as follows.

    If the code in question is a class or method definition, and no ExecutionContext is available, request one from the caller by adding an implicit parameter list:

    def myMethod(myParam: MyType)(implicit ec: ExecutionContext) = …
    //Or
    class MyClass(myParam: MyType)(implicit ec: ExecutionContext) { … }

    This allows the caller of the method, or creator of the instance of the class, to decide which ExecutionContext should be used.

    For typical REPL usage and experimentation, importing the global ExecutionContext is often desired.

    import scala.concurrent.ExcutionContext.Implicits.global

    Specifying Durations

    Operations often require a duration to be specified. A duration DSL is available to make defining these easier:

    import scala.concurrent.duration._
    val d: Duration = 10.seconds

    Using Futures For Non-blocking Computation

    Basic use of futures is easy with the factory method on Future, which executes a provided function asynchronously, handing you back a future result of that function without blocking the current thread. In order to create the Future you will need either an implicit or explicit ExecutionContext to be provided:

    import scala.concurrent._
    import ExecutionContext.Implicits.global  // implicit execution context
    
    val firstZebra: Future[Int] = Future {
      val source = scala.io.Source.fromFile("/etc/dictionaries-common/words")
      source.toSeq.indexOfSlice("zebra")
    }

    Avoid Blocking

    Although blocking is possible in order to await results (with a mandatory timeout duration):

    import scala.concurrent.duration._
    Await.result(firstZebra, 10.seconds)

    and although this is sometimes necessary to do, in particular for testing purposes, blocking in general is discouraged when working with Futures and concurrency in order to avoid potential deadlocks and improve performance. Instead, use callbacks or combinators to remain in the future domain:

    val animalRange: Future[Int] = for {
      aardvark <- firstAardvark
      zebra <- firstZebra
    } yield zebra - aardvark
    
    animalRange.onSuccess {
      case x if x > 500000 => println("It's a long way from Aardvark to Zebra")
    }
    Definition Classes
    scala
  • package duration
    Definition Classes
    concurrent
  • object Duration extends Serializable
    Definition Classes
    duration
  • DurationIsOrdered
  • Infinite

sealed abstract class Infinite extends Duration

Source
Duration.scala
Linear Supertypes
Duration, math.Ordered[Duration], Comparable[Duration], Serializable, java.io.Serializable, AnyRef, Any
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. Infinite
  2. Duration
  3. Ordered
  4. Comparable
  5. Serializable
  6. Serializable
  7. AnyRef
  8. Any
Implicitly
  1. by orderingToOrdered
  2. by durationToPair
  3. by any2stringadd
  4. by StringFormat
  5. by Ensuring
  6. by ArrowAssoc
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. All

Abstract Value Members

  1. abstract def compare(that: Duration): Int

    Result of comparing this with operand that.

    Result of comparing this with operand that.

    Implement this method to determine how instances of A will be sorted.

    Returns x where:

    • x < 0 when this < that
    • x == 0 when this == that
    • x > 0 when this > that
    Definition Classes
    Ordered
  2. abstract def toUnit(unit: TimeUnit): Double

    Return the number of nanoseconds as floating point number, scaled down to the given unit.

    Return the number of nanoseconds as floating point number, scaled down to the given unit. The result may not precisely represent this duration due to the Double datatype's inherent limitations (mantissa size effectively 53 bits). Non-finite durations are represented as

    Definition Classes
    Duration
  3. abstract def unary_-: Duration

    Negate this duration.

    Negate this duration. The only two values which are mapped to themselves are Duration.Zero and Duration.Undefined.

    Definition Classes
    Duration

Concrete Value Members

  1. def *(factor: Double): Duration

    Return this duration multiplied by the scalar factor.

    Return this duration multiplied by the scalar factor. When involving non-finite factors the semantics match those of Double.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException in case of a finite overflow: the range of a finite duration is +-(2^63-1)ns, and no conversion to infinite durations takes place.

  2. def +(other: Duration): Duration

    Return the sum of that duration and this.

    Return the sum of that duration and this. When involving non-finite summands the semantics match those of Double.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException in case of a finite overflow: the range of a finite duration is +-(2^63-1)ns, and no conversion to infinite durations takes place.

  3. def -(other: Duration): Duration

    Return the difference of that duration and this.

    Return the difference of that duration and this. When involving non-finite summands the semantics match those of Double.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException in case of a finite overflow: the range of a finite duration is +-(2^63-1)ns, and no conversion to infinite durations takes place.

  4. def /(divisor: Duration): Double

    Return the quotient of this and that duration as floating-point number.

    Return the quotient of this and that duration as floating-point number. The semantics are determined by Double as if calculating the quotient of the nanosecond lengths of both factors.

    Definition Classes
    InfiniteDuration
  5. def /(divisor: Double): Duration

    Return this duration divided by the scalar factor.

    Return this duration divided by the scalar factor. When involving non-finite factors the semantics match those of Double.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException in case of a finite overflow: the range of a finite duration is +-(2^63-1)ns, and no conversion to infinite durations takes place.

  6. def <(that: Duration): Boolean

    Returns true if this is less than that

    Returns true if this is less than that

    Definition Classes
    Ordered
  7. def <=(that: Duration): Boolean

    Returns true if this is less than or equal to that.

    Returns true if this is less than or equal to that.

    Definition Classes
    Ordered
  8. def >(that: Duration): Boolean

    Returns true if this is greater than that.

    Returns true if this is greater than that.

    Definition Classes
    Ordered
  9. def >=(that: Duration): Boolean

    Returns true if this is greater than or equal to that.

    Returns true if this is greater than or equal to that.

    Definition Classes
    Ordered
  10. def compareTo(that: Duration): Int

    Result of comparing this with operand that.

    Result of comparing this with operand that.

    Definition Classes
    Ordered → Comparable
  11. def div(other: Duration): Double

    Return the quotient of this and that duration as floating-point number.

    Return the quotient of this and that duration as floating-point number. The semantics are determined by Double as if calculating the quotient of the nanosecond lengths of both factors.

    Definition Classes
    Duration
  12. def div(divisor: Double): Duration

    Return this duration divided by the scalar factor.

    Return this duration divided by the scalar factor. When involving non-finite factors the semantics match those of Double.

    Definition Classes
    Duration
    Exceptions thrown

    IllegalArgumentException in case of a finite overflow: the range of a finite duration is +-(2^63-1)ns, and no conversion to infinite durations takes place.

  13. def gt(other: Duration): Boolean
    Definition Classes
    Duration
  14. def gteq(other: Duration): Boolean
    Definition Classes
    Duration
  15. final def isFinite(): Boolean

    This method returns whether this duration is finite, which is not the same as !isInfinite for Double because this method also returns false for Duration.Undefined.

    This method returns whether this duration is finite, which is not the same as !isInfinite for Double because this method also returns false for Duration.Undefined.

    Definition Classes
    InfiniteDuration
  16. final def length: Long

    Obtain the length of this Duration measured in the unit obtained by the unit method.

    Obtain the length of this Duration measured in the unit obtained by the unit method.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException when invoked on a non-finite duration

  17. def lt(other: Duration): Boolean
    Definition Classes
    Duration
  18. def lteq(other: Duration): Boolean
    Definition Classes
    Duration
  19. def max(other: Duration): Duration

    Return the larger of this and that duration as determined by the natural ordering.

    Return the larger of this and that duration as determined by the natural ordering.

    Definition Classes
    Duration
  20. def min(other: Duration): Duration

    Return the smaller of this and that duration as determined by the natural ordering.

    Return the smaller of this and that duration as determined by the natural ordering.

    Definition Classes
    Duration
  21. def minus(other: Duration): Duration

    Return the difference of that duration and this.

    Return the difference of that duration and this. When involving non-finite summands the semantics match those of Double.

    Definition Classes
    Duration
    Exceptions thrown

    IllegalArgumentException in case of a finite overflow: the range of a finite duration is +-(2^63-1)ns, and no conversion to infinite durations takes place.

  22. def mul(factor: Double): Duration

    Return this duration multiplied by the scalar factor.

    Return this duration multiplied by the scalar factor. When involving non-finite factors the semantics match those of Double.

    Definition Classes
    Duration
    Exceptions thrown

    IllegalArgumentException in case of a finite overflow: the range of a finite duration is +-(2^63-1)ns, and no conversion to infinite durations takes place.

  23. def neg(): Duration

    Negate this duration.

    Negate this duration. The only two values which are mapped to themselves are Duration.Zero and Duration.Undefined.

    Definition Classes
    Duration
  24. def plus(other: Duration): Duration

    Return the sum of that duration and this.

    Return the sum of that duration and this. When involving non-finite summands the semantics match those of Double.

    Definition Classes
    Duration
    Exceptions thrown

    IllegalArgumentException in case of a finite overflow: the range of a finite duration is +-(2^63-1)ns, and no conversion to infinite durations takes place.

  25. def productArity: Int

    The arity of this product.

    The arity of this product.

    returns

    2

    Implicit
    This member is added by an implicit conversion from Infinite to (Long, TimeUnit) performed by method durationToPair in scala.concurrent.duration.
    Definition Classes
    Product2Product
  26. def productElement(n: Int): Any

    Returns the n-th projection of this product if 0 <= n < productArity, otherwise throws an IndexOutOfBoundsException.

    Returns the n-th projection of this product if 0 <= n < productArity, otherwise throws an IndexOutOfBoundsException.

    n

    number of the projection to be returned

    returns

    same as ._(n+1), for example productElement(0) is the same as ._1.

    Implicit
    This member is added by an implicit conversion from Infinite to (Long, TimeUnit) performed by method durationToPair in scala.concurrent.duration.
    Definition Classes
    Product2Product
    Annotations
    @throws( clazz = classOf[IndexOutOfBoundsException] )
    Exceptions thrown
  27. def swap: (TimeUnit, Long)

    Swaps the elements of this Tuple.

    Swaps the elements of this Tuple.

    returns

    a new Tuple where the first element is the second element of this Tuple and the second element is the first element of this Tuple.

    Implicit
    This member is added by an implicit conversion from Infinite to (Long, TimeUnit) performed by method durationToPair in scala.concurrent.duration.
    Definition Classes
    Tuple2
  28. final def toCoarsest: Duration

    Return duration which is equal to this duration but with a coarsest Unit, or self in case it is already the coarsest Unit

    Return duration which is equal to this duration but with a coarsest Unit, or self in case it is already the coarsest Unit

    Examples:

    Duration(60, MINUTES).toCoarsest // Duration(1, HOURS)
    Duration(1000, MILLISECONDS).toCoarsest // Duration(1, SECONDS)
    Duration(48, HOURS).toCoarsest // Duration(2, DAYS)
    Duration(5, SECONDS).toCoarsest // Duration(5, SECONDS)
    Definition Classes
    InfiniteDuration
  29. final def toDays: Long

    Return the length of this duration measured in whole days, rounding towards zero.

    Return the length of this duration measured in whole days, rounding towards zero.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException when invoked on a non-finite duration

  30. final def toHours: Long

    Return the length of this duration measured in whole hours, rounding towards zero.

    Return the length of this duration measured in whole hours, rounding towards zero.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException when invoked on a non-finite duration

  31. final def toMicros: Long

    Return the length of this duration measured in whole microseconds, rounding towards zero.

    Return the length of this duration measured in whole microseconds, rounding towards zero.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException when invoked on a non-finite duration

  32. final def toMillis: Long

    Return the length of this duration measured in whole milliseconds, rounding towards zero.

    Return the length of this duration measured in whole milliseconds, rounding towards zero.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException when invoked on a non-finite duration

  33. final def toMinutes: Long

    Return the length of this duration measured in whole minutes, rounding towards zero.

    Return the length of this duration measured in whole minutes, rounding towards zero.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException when invoked on a non-finite duration

  34. final def toNanos: Long

    Return the length of this duration measured in whole nanoseconds, rounding towards zero.

    Return the length of this duration measured in whole nanoseconds, rounding towards zero.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException when invoked on a non-finite duration

  35. final def toSeconds: Long

    Return the length of this duration measured in whole seconds, rounding towards zero.

    Return the length of this duration measured in whole seconds, rounding towards zero.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException when invoked on a non-finite duration

  36. final def unit: TimeUnit

    Obtain the time unit in which the length of this duration is measured.

    Obtain the time unit in which the length of this duration is measured.

    Definition Classes
    InfiniteDuration
    Exceptions thrown

    IllegalArgumentException when invoked on a non-finite duration

Shadowed Implicit Value Members

  1. def <(that: Infinite): Boolean

    Returns true if this is less than that

    Returns true if this is less than that

    Implicit
    This member is added by an implicit conversion from Infinite to math.Ordered[Infinite] performed by method orderingToOrdered in scala.math.Ordered. This conversion will take place only if an implicit value of type math.Ordering[Infinite] is in scope.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (infinite: math.Ordered[Infinite]).<(that)
    Definition Classes
    Ordered
  2. def <=(that: Infinite): Boolean

    Returns true if this is less than or equal to that.

    Returns true if this is less than or equal to that.

    Implicit
    This member is added by an implicit conversion from Infinite to math.Ordered[Infinite] performed by method orderingToOrdered in scala.math.Ordered. This conversion will take place only if an implicit value of type math.Ordering[Infinite] is in scope.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (infinite: math.Ordered[Infinite]).<=(that)
    Definition Classes
    Ordered
  3. def >(that: Infinite): Boolean

    Returns true if this is greater than that.

    Returns true if this is greater than that.

    Implicit
    This member is added by an implicit conversion from Infinite to math.Ordered[Infinite] performed by method orderingToOrdered in scala.math.Ordered. This conversion will take place only if an implicit value of type math.Ordering[Infinite] is in scope.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (infinite: math.Ordered[Infinite]).>(that)
    Definition Classes
    Ordered
  4. def >=(that: Infinite): Boolean

    Returns true if this is greater than or equal to that.

    Returns true if this is greater than or equal to that.

    Implicit
    This member is added by an implicit conversion from Infinite to math.Ordered[Infinite] performed by method orderingToOrdered in scala.math.Ordered. This conversion will take place only if an implicit value of type math.Ordering[Infinite] is in scope.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (infinite: math.Ordered[Infinite]).>=(that)
    Definition Classes
    Ordered
  5. def compare(that: Infinite): Int

    Result of comparing this with operand that.

    Result of comparing this with operand that.

    Implement this method to determine how instances of A will be sorted.

    Returns x where:

    • x < 0 when this < that
    • x == 0 when this == that
    • x > 0 when this > that
    Implicit
    This member is added by an implicit conversion from Infinite to math.Ordered[Infinite] performed by method orderingToOrdered in scala.math.Ordered. This conversion will take place only if an implicit value of type math.Ordering[Infinite] is in scope.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (infinite: math.Ordered[Infinite]).compare(that)
    Definition Classes
    Ordered
  6. def compareTo(that: Infinite): Int

    Result of comparing this with operand that.

    Result of comparing this with operand that.

    Implicit
    This member is added by an implicit conversion from Infinite to math.Ordered[Infinite] performed by method orderingToOrdered in scala.math.Ordered. This conversion will take place only if an implicit value of type math.Ordering[Infinite] is in scope.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (infinite: math.Ordered[Infinite]).compareTo(that)
    Definition Classes
    Ordered → Comparable
  7. def toString(): String

    Creates a String representation of this object.

    Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.

    returns

    a String representation of the object.

    Implicit
    This member is added by an implicit conversion from Infinite to (Long, TimeUnit) performed by method durationToPair in scala.concurrent.duration.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (infinite: (Long, TimeUnit)).toString()
    Definition Classes
    Tuple2 → AnyRef → Any