scala.collection.JavaConversions

object JavaConversions extends WrapAsScala with WrapAsJava

A collection of implicit conversions supporting interoperability between Scala and Java collections.

The following conversions are supported:

scala.collection.Iterable <=> java.lang.Iterable
scala.collection.Iterable <=> java.util.Collection
scala.collection.Iterator <=> java.util.{ Iterator, Enumeration }
scala.collection.mutable.Buffer <=> java.util.List
scala.collection.mutable.Set <=> java.util.Set
scala.collection.mutable.Map <=> java.util.{ Map, Dictionary }
scala.collection.concurrent.Map <=> java.util.concurrent.ConcurrentMap

In all cases, converting from a source type to a target type and back again will return the original source object, eg.

import scala.collection.JavaConversions._

val sl = new scala.collection.mutable.ListBuffer[Int]
val jl : java.util.List[Int] = sl
val sl2 : scala.collection.mutable.Buffer[Int] = jl
assert(sl eq sl2)

In addition, the following one way conversions are provided:

scala.collection.Seq         => java.util.List
scala.collection.mutable.Seq => java.util.List
scala.collection.Set         => java.util.Set
scala.collection.Map         => java.util.Map
java.util.Properties         => scala.collection.mutable.Map[String, String]

Value Members From scala.collection.convert.WrapAsJava

implicit def asJavaCollection[A](it: Iterable[A]): Collection[A]

Implicitly converts a Scala Iterable to an immutable Java Collection.

If the Scala Iterable was previously obtained from an implicit or explicit call of asSizedIterable(java.util.Collection) then the original Java Collection will be returned.

  • it
    • The SizedIterable to be converted.
  • returns
    • A Java Collection view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def asJavaDictionary[A, B](m: mutable.Map[A, B]): Dictionary[A, B]

Implicitly converts a Scala mutable Map to a Java Dictionary .

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

If the Scala Dictionary was previously obtained from an implicit or explicit call of asMap(java.util.Dictionary) then the original Java Dictionary will be returned.

  • m
    • The Map to be converted.
  • returns
    • A Java Dictionary view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def asJavaEnumeration[A](it: Iterator[A]): java.util.Enumeration[A]

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

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

  • it
    • The Iterator to be converted.
  • returns
    • A Java Enumeration view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def asJavaIterable[A](i: Iterable[A]): java.lang.Iterable[A]

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

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

  • i
    • The Iterable to be converted.
  • returns
    • A Java Iterable view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def asJavaIterator[A](it: Iterator[A]): java.util.Iterator[A]

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

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

  • it
    • The Iterator to be converted.
  • returns
    • A Java Iterator view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def bufferAsJavaList[A](b: Buffer[A]): java.util.List[A]

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

If the Scala Buffer was previously obtained from an implicit or explicit call of asBuffer(java.util.List) then the original Java List will be returned.

  • b
    • The Buffer to be converted.
  • returns
    • A Java List view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def mapAsJavaConcurrentMap[A, B](m: concurrent.Map[A, B]): ConcurrentMap[A, B]

Implicitly converts a Scala mutable concurrent.Map to a Java ConcurrentMap .

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

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

  • m
    • The Scala concurrent.Map to be converted.
  • returns
    • A Java ConcurrentMap view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def mapAsJavaMap[A, B](m: Map[A, B]): java.util.Map[A, B]

Implicitly converts a Scala Map to a Java Map .

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

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

  • m
    • The Map to be converted.
  • returns
    • A Java Map view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def mutableMapAsJavaMap[A, B](m: mutable.Map[A, B]): java.util.Map[A, B]

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

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

  • m
    • The Map to be converted.
  • returns
    • A Java Map view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def mutableSeqAsJavaList[A](seq: mutable.Seq[A]): java.util.List[A]

Implicitly converts a Scala mutable Seq to a Java List. The returned Java List is backed by the provided Scala Seq and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.

If the Scala Seq was previously obtained from an implicit or explicit call of asSeq(java.util.List) then the original Java List will be returned.

  • seq
    • The Seq to be converted.
  • returns
    • A Java List view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def mutableSetAsJavaSet[A](s: mutable.Set[A]): java.util.Set[A]

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

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

  • s
    • The Set to be converted.
  • returns
    • A Java Set view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def seqAsJavaList[A](seq: Seq[A]): java.util.List[A]

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

If the Scala Seq was previously obtained from an implicit or explicit call of asSeq(java.util.List) then the original Java List will be returned.

  • seq
    • The Seq to be converted.
  • returns
    • A Java List view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

implicit def setAsJavaSet[A](s: Set[A]): java.util.Set[A]

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

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

  • s
    • The Set to be converted.
  • returns
    • A Java Set view of the argument.
  • Definition Classes
    • WrapAsJava

(defined at scala.collection.convert.WrapAsJava)

Value Members From scala.collection.convert.WrapAsScala

implicit def asScalaBuffer[A](l: java.util.List[A]): Buffer[A]

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 asScalaBuffer(scala.collection.mutable.Buffer) then the original Scala Buffer will be returned.

  • l
    • The List to be converted.
  • returns
    • A Scala mutable Buffer view of the argument.
  • Definition Classes
    • WrapAsScala

(defined at scala.collection.convert.WrapAsScala)

implicit def asScalaIterator[A](it: java.util.Iterator[A]): Iterator[A]

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.

  • it
    • The Iterator to be converted.
  • returns
    • A Scala Iterator view of the argument.
  • Definition Classes
    • WrapAsScala

(defined at scala.collection.convert.WrapAsScala)

implicit def asScalaSet[A](s: java.util.Set[A]): mutable.Set[A]

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 asScalaSet(scala.collection.mutable.Set) then the original Scala Set will be returned.

  • s
    • The Set to be converted.
  • returns
    • A Scala mutable Set view of the argument.
  • Definition Classes
    • WrapAsScala

(defined at scala.collection.convert.WrapAsScala)

implicit def collectionAsScalaIterable[A](i: Collection[A]): Iterable[A]

Implicitly converts a Java Collection to an Scala Iterable .

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

  • i
    • The Collection to be converted.
  • returns
    • A Scala Iterable view of the argument.
  • Definition Classes
    • WrapAsScala

(defined at scala.collection.convert.WrapAsScala)

implicit def dictionaryAsScalaMap[A, B](p: Dictionary[A, B]): mutable.Map[A, B]

Implicitly converts a Java Dictionary to a Scala mutable Map .

The returned Scala Map 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
    • A Scala mutable Map view of the argument.
  • Definition Classes
    • WrapAsScala

(defined at scala.collection.convert.WrapAsScala)

implicit def enumerationAsScalaIterator[A](i: java.util.Enumeration[A]): Iterator[A]

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 enumerationAsScalaIterator(scala.collection.Iterator) then the original Scala Iterator will be returned.

  • i
    • The Enumeration to be converted.
  • returns
    • A Scala Iterator view of the argument.
  • Definition Classes
    • WrapAsScala

(defined at scala.collection.convert.WrapAsScala)

implicit def iterableAsScalaIterable[A](i: java.lang.Iterable[A]): Iterable[A]

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 iterableAsScalaIterable(scala.collection.Iterable) then the original Scala Iterable will be returned.

  • i
    • The Iterable to be converted.
  • returns
    • A Scala Iterable view of the argument.
  • Definition Classes
    • WrapAsScala

(defined at scala.collection.convert.WrapAsScala)

implicit def mapAsScalaConcurrentMap[A, B](m: ConcurrentMap[A, B]): concurrent.Map[A, B]

Implicitly converts a Java ConcurrentMap to a Scala mutable ConcurrentMap. The returned Scala ConcurrentMap 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 asConcurrentMap(scala.collection.mutable.ConcurrentMap) then the original Scala ConcurrentMap will be returned.

  • m
    • The ConcurrentMap to be converted.
  • returns
    • A Scala mutable ConcurrentMap view of the argument.
  • Definition Classes
    • WrapAsScala

(defined at scala.collection.convert.WrapAsScala)

implicit def mapAsScalaMap[A, B](m: java.util.Map[A, B]): mutable.Map[A, B]

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 mapAsScalaMap(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
    • A Scala mutable Map view of the argument.
  • Definition Classes
    • WrapAsScala

(defined at scala.collection.convert.WrapAsScala)

implicit def propertiesAsScalaMap(p: Properties): mutable.Map[String, String]

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
    • A Scala mutable Map[String, String] view of the argument.
  • Definition Classes
    • WrapAsScala (defined at scala.collection.convert.WrapAsScala)

Full Source:

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2006-2013, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://www.scala-lang.org/           **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */

package scala
package collection

import convert._

/**   A collection of implicit conversions supporting interoperability between
 *    Scala and Java collections.
 *
 *    The following conversions are supported:
 *{{{
 *    scala.collection.Iterable <=> java.lang.Iterable
 *    scala.collection.Iterable <=> java.util.Collection
 *    scala.collection.Iterator <=> java.util.{ Iterator, Enumeration }
 *    scala.collection.mutable.Buffer <=> java.util.List
 *    scala.collection.mutable.Set <=> java.util.Set
 *    scala.collection.mutable.Map <=> java.util.{ Map, Dictionary }
 *    scala.collection.concurrent.Map <=> java.util.concurrent.ConcurrentMap
 *}}}
 *    In all cases, converting from a source type to a target type and back
 *    again will return the original source object, eg.
 *
 *{{{
 *    import scala.collection.JavaConversions._
 *
 *    val sl = new scala.collection.mutable.ListBuffer[Int]
 *    val jl : java.util.List[Int] = sl
 *    val sl2 : scala.collection.mutable.Buffer[Int] = jl
 *    assert(sl eq sl2)
 *}}}
 *  In addition, the following one way conversions are provided:
 *
 *{{{
 *    scala.collection.Seq         => java.util.List
 *    scala.collection.mutable.Seq => java.util.List
 *    scala.collection.Set         => java.util.Set
 *    scala.collection.Map         => java.util.Map
 *    java.util.Properties         => scala.collection.mutable.Map[String, String]
 *}}}
 *
 *  @author Miles Sabin
 *  @author Martin Odersky
 *  @since  2.8
 */
object JavaConversions extends WrapAsScala with WrapAsJava