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    /*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2006-2010, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://www.scala-lang.org/           **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */



package scala.collection

/** 
    
 *    A collection of decorators that allow to convert between
 *    Scala and Java collections using `asScala` and `asJava` methods.
 *  
    
 *  
    
 *    The following conversions are supported via `asJava`, `asScala`
 *  
    
 *  
      
 *    
    • scala.collection.Iterable <=> java.lang.Iterable
      • 
 *    
    • scala.collection.Iterator <=> java.util.Iterator
      • 
 *    
    • scala.collection.mutable.Buffer <=> java.util.List
      • 
 *    
    • scala.collection.mutable.Set <=> java.util.Set
      • 
 *    
    • scala.collection.mutable.Map <=> java.util.Map
      • 
 *    
    • scala.collection.mutable.ConcurrentMap <=> 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, e.g.
 *  
    
 *  
     *    import scala.collection.JavaConverters._
 * 
 *    val sl = new scala.collection.mutable.ListBuffer[Int]
 *    val jl : java.util.List[Int] = sl.asJava
 *    val sl2 : scala.collection.mutable.Buffer[Int] = jl.asScala
 *    assert(sl eq sl2)g
    
 *  
    
 *  
    
 *    The following conversions also are supported, but the
 *    direction Scala to Java is done my a more specifically named method:
 *    `asJavaCollection`, `asJavaEnumeration`, `asJavaDictionary`.
 *  
    
 *  
      
 *    
    • scala.collection.Iterable <=> java.util.Collection
      • 
 *    
    • scala.collection.Iterator <=> java.util.Enumeration
      • 
 *    
    • scala.collection.mutable.Map <=> java.util.Dictionary
      • 
 *  
    
 *  In addition, the following one way conversions are provided via `asJava`:
 *  
    
 *  
      
 *    
    • 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
      • 
 *  
    
 * 
 *  @author Martin Odersky
 *  @since  2.8.1
 */
object JavaConverters {
  import java.{ lang => jl, util => ju }
  import java.util.{ concurrent => juc }
  import JavaConversions._

  // Conversion decorator classes
  
  /** Generic class containing the `asJava` converter method */
  class AsJava[C](op: => C) {
    /** Converts a Scala collection to the corresponding Java collection */
    def asJava: C = op
  }

  /** Generic class containing the `asScala` converter method */
  class AsScala[C](op: => C) {
    /** Converts a Java collection to the corresponding Scala collection */
    def asScala: C = op
  }

  /** Generic class containing the `asJavaCollection` converter method */
  class AsJavaCollection[A](i: Iterable[A]) {
    /** Converts a Scala `Iterable` to a Java `Collection` */
    def asJavaCollection: ju.Collection[A] = JavaConversions.asJavaCollection(i)
  }

  /** Generic class containing the `asJavaEnumeration` converter method */
  class AsJavaEnumeration[A](i: Iterator[A]) {
    /** Converts a Scala `Iterator` to a Java `Enumeration` */
    def asJavaEnumeration: ju.Enumeration[A] = JavaConversions.asJavaEnumeration(i)
  }

  /** Generic class containing the `asJavaDictionary` converter method */
  class AsJavaDictionary[A, B](m : mutable.Map[A, B]) {
    /** Converts a Scala `Map` to a Java `Dictionary` */
    def asJavaDictionary: ju.Dictionary[A, B] = JavaConversions.asJavaDictionary(m)
  }
    
  // Scala => Java
  
  /**
   * Adds an `asJava` method that 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 by the `asJava` method.
   * 
   * @param i The Iterator to be converted.
   * @return An object with an `asJava` method that returns a Java Iterator view of the argument. 
   */
  implicit def asJavaIteratorConverter[A](i : Iterator[A]): AsJava[ju.Iterator[A]] = 
    new AsJava(asJavaIterator(i))

  /**
   * Adds an `asJavaEnumeration` method that 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.
   * 
   * @param i The Iterator to be converted.
   * @return An object with an `asJavaEnumeration` method that returns a Java Enumeration view of the argument.
   */
  implicit def asJavaEnumerationConverter[A](i : Iterator[A]): AsJavaEnumeration[A] = 
    new AsJavaEnumeration(i)

  /**
   * Adds an `asJava` method that 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.
   * 
   * @param i The Iterable to be converted.
   * @return An object with an `asJavaCollection` method that returns a Java Iterable view of the argument.
   */
  implicit def asJavaIterableConverter[A](i : Iterable[A]): AsJava[jl.Iterable[A]] = 
    new AsJava(asJavaIterable(i))

  /**
   * Adds an `asJavaCollection` method that 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.
   * 
   * @param i The SizedIterable to be converted.
   * @return An object with an `asJava` method that returns a Java Collection view of the argument.
   */
  implicit def asJavaCollectionConverter[A](i : Iterable[A]): AsJavaCollection[A] = 
    new AsJavaCollection(i)

  /**
   * Adds an `asJava` method that 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.
   * 
   * @param b The Buffer to be converted.
   * @return An object with an `asJava` method that returns a Java List view of the argument.
   */
  implicit def asJavaListConverter[A](b : mutable.Buffer[A]): AsJava[ju.List[A]] = 
    new AsJava(asJavaList(b))
    
  /**
   * Adds an `asJava` method that 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.
   * 
   * @param b The Seq to be converted.
   * @return An object with an `asJava` method that returns a Java List view of the argument.
   */
  implicit def asJavaListConverter[A](b : mutable.Seq[A]): AsJava[ju.List[A]] = 
    new AsJava(asJavaList(b))
    
  /**
   * Adds an `asJava` method that 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.
   * 
   * @param b The Seq to be converted.
   * @return An object with an `asJava` method that returns a Java List view of the argument.
   */
  implicit def asJavaListConverter[A](b : Seq[A]): AsJava[ju.List[A]] = 
    new AsJava(asJavaList(b))
    
  /**
   * Adds an `asJava` method that 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.
   * 
   * @param s The Set to be converted.
   * @return An object with an `asJava` method that returns a Java Set view of the argument.
   */
  implicit def asJavaSetConverter[A](s : mutable.Set[A]): AsJava[ju.Set[A]] = 
    new AsJava(asJavaSet(s))

  /**
   * Adds an `asJava` method that 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.
   * 
   * @param s The Set to be converted.
   * @return An object with an `asJava` method that returns a Java Set view of the argument.
   */
  implicit def asJavaSetConverter[A](s : Set[A]): AsJava[ju.Set[A]] = 
    new AsJava(asJavaSet(s))

  /**
   * Adds an `asJava` method that 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.
   * 
   * @param m The Map to be converted.
   * @return An object with an `asJava` method that returns a Java Map view of the argument.
   */
  implicit def asJavaMapConverter[A, B](m : mutable.Map[A, B]): AsJava[ju.Map[A, B]] = 
    new AsJava(asJavaMap(m))

  /**
   * Adds an `asJavaDictionary` method that 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.
   * 
   * @param m The Map to be converted.
   * @return An object with an `asJavaDictionary` method that returns a Java Dictionary view of the argument.
   */
  implicit def asJavaDictionaryConverter[A, B](m : mutable.Map[A, B]): AsJavaDictionary[A, B] = 
    new AsJavaDictionary(m)

  /**
   * Adds an `asJava` method that 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.
   * 
   * @param m The Map to be converted.
   * @return An object with an `asJava` method that returns a Java Map view of the argument.
   */
  implicit def asJavaMapConverter[A, B](m : Map[A, B]): AsJava[ju.Map[A, B]] = 
    new AsJava(asJavaMap(m))

  /**
   * Adds an `asJava` method that implicitly converts a Scala mutable `ConcurrentMap` to a Java `ConcurrentMap`.
   * The returned Java `ConcurrentMap` is backed by the provided Scala `ConcurrentMap`
   * and any side-effects of using it via the Java interface will be visible
   * via the Scala interface and vice versa.
   * 
    
   * If the Scala ConcurrentMap was previously obtained from an implicit or
   * explicit call of asConcurrentMap(java.util.concurrect.ConcurrentMap) then the original
   * Java ConcurrentMap will be returned.
   * 
   * @param m The ConcurrentMap to be converted.
   * @return An object with an `asJava` method that returns a Java ConcurrentMap view of the argument.
   */
  implicit def asJavaConcurrentMapConverter[A, B](m: mutable.ConcurrentMap[A, B]): AsJava[juc.ConcurrentMap[A, B]] = 
    new AsJava(asJavaConcurrentMap(m))

  /**
   * 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.
   * 
   * @param i The Iterator to be converted.
   * @return An object with an `asScala` method that returns a Scala Iterator view of the argument.
   */
  implicit def asScalaIteratorConverter[A](i : ju.Iterator[A]): AsScala[Iterator[A]] = 
    new AsScala(asScalaIterator(i))

  /**
   * 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.
   * 
   * @param i The Enumeration to be converted.
   * @return An object with an `asScala` method that returns a Scala Iterator view of the argument.
   */
  implicit def enumerationAsScalaIteratorConverter[A](i : ju.Enumeration[A]): AsScala[Iterator[A]] = 
    new AsScala(enumerationAsScalaIterator(i))

  /**
   * 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.
   * 
   * @param i The Iterable to be converted.
   * @return An object with an `asScala` method that returns a Scala Iterable view of the argument.
   */
  implicit def asScalaIterableConverter[A](i : jl.Iterable[A]): AsScala[Iterable[A]] = 
    new AsScala(asScalaIterable(i))

  /**
   * 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.
   * 
   * @param i The Collection to be converted.
   * @return An object with an `asScala` method that returns a Scala SizedIterable view of the argument.
   */
  implicit def asScalaIterableConverter[A](i : ju.Collection[A]): AsScala[Iterable[A]] = 
    new AsScala(asScalaIterable(i))

  /**
   * 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.
   * 
   * @param l The List to be converted.
   * @return An object with an `asScala` method that returns a Scala mutable Buffer view of the argument.
   */
  implicit def asScalaBufferConverter[A](l : ju.List[A]): AsScala[mutable.Buffer[A]] = 
    new AsScala(asScalaBuffer(l))

  /**
   * 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
   * ScalaThe reported problems have to do with dependent method types, which is currently an experimental feature in Scala and is still under development. We emphasize that these problems are related to type-inference and, as stated in the paper, it is possible to run and type-check the programs with additional annotations. Set will be returned.
   * 
   * @param s The Set to be converted.
   * @return An object with an `asScala` method that returns a Scala mutable Set view of the argument.
   */
  implicit def asScalaSetConverter[A](s : ju.Set[A]): AsScala[mutable.Set[A]] = 
    new AsScala(asScalaSet(s))

  /**
   * 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.
   * 
   * @param m The Map to be converted.
   * @return An object with an `asScala` method that returns a Scala mutable Map view of the argument.
   */
  implicit def asScalaMapConverter[A, B](m : ju.Map[A, B]): AsScala[mutable.Map[A, B]] = 
    new AsScala(asScalaMap(m))

  /**
   * Adds an `asScala` method that 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.
   * 
   * @param m The ConcurrentMap to be converted.
   * @return An object with an `asScala` method that returns a Scala mutable ConcurrrentMap view of the argument.
   */
  implicit def asScalaConcurrentMapConverter[A, B](m: juc.ConcurrentMap[A, B]): AsScala[mutable.ConcurrentMap[A, B]] = 
    new AsScala(asScalaConcurrentMap(m))

  /**
   * 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.
   * 
   * @param m The Dictionary to be converted.
   * @return An object with an `asScala` method that returns a Scala mutable Map[String, String] view of the argument.
   */
  implicit def dictionaryAsScalaMapConverter[A, B](p: ju.Dictionary[A, B]): AsScala[mutable.Map[A, B]] =
    new AsScala(dictionaryAsScalaMap(p))
      
  /**
   * 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.
   * 
   * @param m The Properties to be converted.
   * @return An object with an `asScala` method that returns a Scala mutable Map[String, String] view of the argument.
   */
  implicit def asScalaMapConverter(p: ju.Properties): AsScala[mutable.Map[String, String]] = 
    new AsScala(asScalaMap(p))
    
}




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