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 left.

    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, including an example implementation of a JSON parser (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 collection

    Contains the base traits and objects needed to use and extend Scala's collection library.

    Contains the base traits and objects needed to use and extend Scala's collection library.

    Guide

    A detailed guide for using the collections library is available at http://docs.scala-lang.org/overviews/collections/introduction.html. Developers looking to extend the collections library can find a description of its architecture at http://docs.scala-lang.org/overviews/core/architecture-of-scala-collections.html.

    Using Collections

    It is convenient to treat all collections as either a scala.collection.Traversable or scala.collection.Iterable, as these traits define the vast majority of operations on a collection.

    Collections can, of course, be treated as specifically as needed, and the library is designed to ensure that the methods that transform collections will return a collection of the same type:

    scala> val array = Array(1,2,3,4,5,6)
    array: Array[Int] = Array(1, 2, 3, 4, 5, 6)
    
    scala> array map { _.toString }
    res0: Array[String] = Array(1, 2, 3, 4, 5, 6)
    
    scala> val list = List(1,2,3,4,5,6)
    list: List[Int] = List(1, 2, 3, 4, 5, 6)
    
    scala> list map { _.toString }
    res1: List[String] = List(1, 2, 3, 4, 5, 6)

    Creating Collections

    The most common way to create a collection is to use its companion object as a factory. The three most commonly used collections are scala.collection.Seq, scala.collection.immutable.Set, and scala.collection.immutable.Map. They can be used directly as shown below since their companion objects are all available as type aliases in either the scala package or in scala.Predef. New collections are created like this:

    scala> val seq = Seq(1,2,3,4,1)
    seq: Seq[Int] = List(1, 2, 3, 4, 1)
    
    scala> val set = Set(1,2,3,4,1)
    set: scala.collection.immutable.Set[Int] = Set(1, 2, 3, 4)
    
    scala> val map = Map(1 -> "one", 2 -> "two", 3 -> "three", 2 -> "too")
    map: scala.collection.immutable.Map[Int,String] = Map(1 -> one, 2 -> too, 3 -> three)

    It is also typical to prefer the scala.collection.immutable collections over those in scala.collection.mutable; the types aliased in the scala.Predef object are the immutable versions.

    Also note that the collections library was carefully designed to include several implementations of each of the three basic collection types. These implementations have specific performance characteristics which are described in the guide.

    The concrete parallel collections also have specific performance characteristics which are described in the parallel collections guide

    Converting between Java Collections

    The scala.collection.JavaConversions object provides implicit defs that will allow mostly seamless integration between APIs using Java Collections and the Scala collections library.

    Alternatively the scala.collection.JavaConverters object provides a collection of decorators that allow converting between Scala and Java collections using asScala and asJava methods.

    Definition Classes
    scala
  • package convert
    Definition Classes
    collection
  • DecorateAsJava
  • DecorateAsScala
  • WrapAsJava
  • WrapAsScala
t

scala.collection.convert

DecorateAsScala

trait DecorateAsScala extends AnyRef

Source
DecorateAsScala.scala
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  1. DecorateAsScala
  2. AnyRef
  3. Any
Implicitly
  1. by any2stringadd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
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Value Members

  1. final def !=(arg0: Any): Boolean

    Test two objects for inequality.

    Test two objects for inequality.

    returns

    true if !(this == that), false otherwise.

    Definition Classes
    AnyRef → Any
  2. final def ##(): Int

    Equivalent to x.hashCode except for boxed numeric types and null.

    Equivalent to x.hashCode except for boxed numeric types and null. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For null returns a hashcode where null.hashCode throws a NullPointerException.

    returns

    a hash value consistent with ==

    Definition Classes
    AnyRef → Any
  3. def +(other: String): String
    Implicit
    This member is added by an implicit conversion from DecorateAsScala to any2stringadd[DecorateAsScala] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. def ->[B](y: B): (DecorateAsScala, B)
    Implicit
    This member is added by an implicit conversion from DecorateAsScala to ArrowAssoc[DecorateAsScala] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  5. final def ==(arg0: Any): Boolean

    The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

    The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    Definition Classes
    AnyRef → Any
  6. final def asInstanceOf[T0]: T0

    Cast the receiver object to be of type T0.

    Cast the receiver object to be of type T0.

    Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression 1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expression List(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.

    returns

    the receiver object.

    Definition Classes
    Any
    Exceptions thrown

    ClassCastException if the receiver object is not an instance of the erasure of type T0.

  7. implicit def asScalaBufferConverter[A](l: java.util.List[A]): Decorators.AsScala[Buffer[A]]

    Adds an asScala method that implicitly converts a Java List to a Scala mutable Buffer.

    Adds an asScala method that implicitly converts a Java List to a Scala mutable Buffer.

    The returned Scala Buffer is backed by the provided Java List and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.

    If the Java List was previously obtained from an implicit or explicit call of asList(scala.collection.mutable.Buffer) then the original Scala Buffer will be returned.

    l

    The List to be converted.

    returns

    An object with an asScala method that returns a Scala mutable Buffer view of the argument.

  8. implicit def asScalaIteratorConverter[A](i: java.util.Iterator[A]): Decorators.AsScala[Iterator[A]]

    Adds an asScala method that implicitly converts a Java Iterator to a Scala Iterator.

    Adds an asScala method that implicitly converts a Java Iterator to a Scala Iterator.

    The returned Scala Iterator is backed by the provided Java Iterator and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.

    If the Java Iterator was previously obtained from an implicit or explicit call of asIterator(scala.collection.Iterator) then the original Scala Iterator will be returned.

    i

    The Iterator to be converted.

    returns

    An object with an asScala method that returns a Scala Iterator view of the argument.

  9. implicit def asScalaSetConverter[A](s: java.util.Set[A]): Decorators.AsScala[mutable.Set[A]]

    Adds an asScala method that implicitly converts a Java Set to a Scala mutable Set.

    Adds an asScala method that implicitly converts a Java Set to a Scala mutable Set.

    The returned Scala Set is backed by the provided Java Set and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.

    If the Java Set was previously obtained from an implicit or explicit call of asSet(scala.collection.mutable.Set) then the original Scala Set will be returned.

    s

    The Set to be converted.

    returns

    An object with an asScala method that returns a Scala mutable Set view of the argument.

  10. def clone(): AnyRef

    Create a copy of the receiver object.

    Create a copy of the receiver object.

    The default implementation of the clone method is platform dependent.

    returns

    a copy of the receiver object.

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
    Note

    not specified by SLS as a member of AnyRef

  11. implicit def collectionAsScalaIterableConverter[A](i: Collection[A]): Decorators.AsScala[Iterable[A]]

    Adds an asScala method that implicitly converts a Java Collection to an Scala Iterable.

    Adds an asScala method that implicitly converts a Java Collection to an Scala Iterable.

    If the Java Collection was previously obtained from an implicit or explicit call of asCollection(scala.collection.SizedIterable) then the original Scala SizedIterable will be returned.

    i

    The Collection to be converted.

    returns

    An object with an asScala method that returns a Scala SizedIterable view of the argument.

  12. implicit def dictionaryAsScalaMapConverter[A, B](p: Dictionary[A, B]): Decorators.AsScala[mutable.Map[A, B]]

    Adds an asScala method that implicitly converts a Java Dictionary to a Scala mutable Map[String, String].

    Adds an asScala method that implicitly converts a Java Dictionary to a Scala mutable Map[String, String]. The returned Scala Map[String, String] is backed by the provided Java Dictionary and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.

    p

    The Dictionary to be converted.

    returns

    An object with an asScala method that returns a Scala mutable Map[String, String] view of the argument.

  13. def ensuring(cond: (DecorateAsScala) ⇒ Boolean, msg: ⇒ Any): DecorateAsScala
    Implicit
    This member is added by an implicit conversion from DecorateAsScala to Ensuring[DecorateAsScala] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  14. def ensuring(cond: (DecorateAsScala) ⇒ Boolean): DecorateAsScala
    Implicit
    This member is added by an implicit conversion from DecorateAsScala to Ensuring[DecorateAsScala] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  15. def ensuring(cond: Boolean, msg: ⇒ Any): DecorateAsScala
    Implicit
    This member is added by an implicit conversion from DecorateAsScala to Ensuring[DecorateAsScala] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  16. def ensuring(cond: Boolean): DecorateAsScala
    Implicit
    This member is added by an implicit conversion from DecorateAsScala to Ensuring[DecorateAsScala] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  17. implicit def enumerationAsScalaIteratorConverter[A](i: java.util.Enumeration[A]): Decorators.AsScala[Iterator[A]]

    Adds an asScala method that implicitly converts a Java Enumeration to a Scala Iterator.

    Adds an asScala method that implicitly converts a Java Enumeration to a Scala Iterator.

    The returned Scala Iterator is backed by the provided Java Enumeration and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.

    If the Java Enumeration was previously obtained from an implicit or explicit call of asEnumeration(scala.collection.Iterator) then the original Scala Iterator will be returned.

    i

    The Enumeration to be converted.

    returns

    An object with an asScala method that returns a Scala Iterator view of the argument.

  18. final def eq(arg0: AnyRef): Boolean

    Tests whether the argument (that) is a reference to the receiver object (this).

    Tests whether the argument (that) is a reference to the receiver object (this).

    The eq method implements an equivalence relation on non-null instances of AnyRef, and has three additional properties:

    • It is consistent: for any non-null instances x and y of type AnyRef, multiple invocations of x.eq(y) consistently returns true or consistently returns false.
    • For any non-null instance x of type AnyRef, x.eq(null) and null.eq(x) returns false.
    • null.eq(null) returns true.

    When overriding the equals or hashCode methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2), they should be equal to each other (o1 == o2) and they should hash to the same value (o1.hashCode == o2.hashCode).

    returns

    true if the argument is a reference to the receiver object; false otherwise.

    Definition Classes
    AnyRef
  19. def equals(arg0: Any): Boolean

    The equality method for reference types.

    The equality method for reference types. Default implementation delegates to eq.

    See also equals in scala.Any.

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    Definition Classes
    AnyRef → Any
  20. def finalize(): Unit

    Called by the garbage collector on the receiver object when there are no more references to the object.

    Called by the garbage collector on the receiver object when there are no more references to the object.

    The details of when and if the finalize method is invoked, as well as the interaction between finalize and non-local returns and exceptions, are all platform dependent.

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
    Note

    not specified by SLS as a member of AnyRef

  21. def formatted(fmtstr: String): String

    Returns string formatted according to given format string.

    Returns string formatted according to given format string. Format strings are as for String.format (@see java.lang.String.format).

    Implicit
    This member is added by an implicit conversion from DecorateAsScala to StringFormat[DecorateAsScala] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  22. final def getClass(): Class[_]

    Returns the runtime class representation of the object.

    Returns the runtime class representation of the object.

    returns

    a class object corresponding to the runtime type of the receiver.

    Definition Classes
    AnyRef → Any
  23. def hashCode(): Int

    The hashCode method for reference types.

    The hashCode method for reference types. See hashCode in scala.Any.

    returns

    the hash code value for this object.

    Definition Classes
    AnyRef → Any
  24. final def isInstanceOf[T0]: Boolean

    Test whether the dynamic type of the receiver object is T0.

    Test whether the dynamic type of the receiver object is T0.

    Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression 1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.

    returns

    true if the receiver object is an instance of erasure of type T0; false otherwise.

    Definition Classes
    Any
  25. implicit def iterableAsScalaIterableConverter[A](i: java.lang.Iterable[A]): Decorators.AsScala[Iterable[A]]

    Adds an asScala method that implicitly converts a Java Iterable to a Scala Iterable.

    Adds an asScala method that implicitly converts a Java Iterable to a Scala Iterable.

    The returned Scala Iterable is backed by the provided Java Iterable and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.

    If the Java Iterable was previously obtained from an implicit or explicit call of asIterable(scala.collection.Iterable) then the original Scala Iterable will be returned.

    i

    The Iterable to be converted.

    returns

    An object with an asScala method that returns a Scala Iterable view of the argument.

  26. implicit def mapAsScalaConcurrentMapConverter[A, B](m: ConcurrentMap[A, B]): Decorators.AsScala[concurrent.Map[A, B]]

    Adds an asScala method that implicitly converts a Java ConcurrentMap to a Scala mutable concurrent.Map.

    Adds an asScala method that implicitly converts a Java ConcurrentMap to a Scala mutable concurrent.Map. The returned Scala concurrent.Map is backed by the provided Java ConcurrentMap and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.

    If the Java ConcurrentMap was previously obtained from an implicit or explicit call of mapAsScalaConcurrentMap(scala.collection.mutable.ConcurrentMap) then the original Scala concurrent.Map will be returned.

    m

    The ConcurrentMap to be converted.

    returns

    An object with an asScala method that returns a Scala mutable concurrent.Map view of the argument.

  27. implicit def mapAsScalaMapConverter[A, B](m: java.util.Map[A, B]): Decorators.AsScala[mutable.Map[A, B]]

    Adds an asScala method that implicitly converts a Java Map to a Scala mutable Map.

    Adds an asScala method that implicitly converts a Java Map to a Scala mutable Map. The returned Scala Map is backed by the provided Java Map and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.

    If the Java Map was previously obtained from an implicit or explicit call of asMap(scala.collection.mutable.Map) then the original Scala Map will be returned.

    If the wrapped map is synchronized (e.g. from java.util.Collections.synchronizedMap), it is your responsibility to wrap all non-atomic operations with underlying.synchronized. This includes get, as java.util.Map's API does not allow for an atomic get when null values may be present.

    m

    The Map to be converted.

    returns

    An object with an asScala method that returns a Scala mutable Map view of the argument.

  28. final def ne(arg0: AnyRef): Boolean

    Equivalent to !(this eq that).

    Equivalent to !(this eq that).

    returns

    true if the argument is not a reference to the receiver object; false otherwise.

    Definition Classes
    AnyRef
  29. final def notify(): Unit

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Definition Classes
    AnyRef
    Note

    not specified by SLS as a member of AnyRef

  30. final def notifyAll(): Unit

    Wakes up all threads that are waiting on the receiver object's monitor.

    Wakes up all threads that are waiting on the receiver object's monitor.

    Definition Classes
    AnyRef
    Note

    not specified by SLS as a member of AnyRef

  31. implicit def propertiesAsScalaMapConverter(p: Properties): Decorators.AsScala[mutable.Map[String, String]]

    Adds an asScala method that implicitly converts a Java Properties to a Scala mutable Map[String, String].

    Adds an asScala method that implicitly converts a Java Properties to a Scala mutable Map[String, String]. The returned Scala Map[String, String] is backed by the provided Java Properties and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.

    p

    The Properties to be converted.

    returns

    An object with an asScala method that returns a Scala mutable Map[String, String] view of the argument.

  32. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  33. 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.

    Definition Classes
    AnyRef → Any
  34. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  35. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  36. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  37. def [B](y: B): (DecorateAsScala, B)
    Implicit
    This member is added by an implicit conversion from DecorateAsScala to ArrowAssoc[DecorateAsScala] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd from DecorateAsScala to any2stringadd[DecorateAsScala]

Inherited by implicit conversion StringFormat from DecorateAsScala to StringFormat[DecorateAsScala]

Inherited by implicit conversion Ensuring from DecorateAsScala to Ensuring[DecorateAsScala]

Inherited by implicit conversion ArrowAssoc from DecorateAsScala to ArrowAssoc[DecorateAsScala]

Ungrouped