Scala example source code file (ImmutableMapAdaptor.scala)

This example Scala source code file (ImmutableMapAdaptor.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Scala source code examples by using tags.

All credit for the original source code belongs to scala-lang.org; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Scala tags/keywords

a, abstractmap, adaptors, annotation, b, boolean, iterable, iterator, map, serializable, unit

The ImmutableMapAdaptor.scala Scala example source code

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2003-2013, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */



package scala
package collection
package mutable

import scala.annotation.migration

/** This class can be used as an adaptor to create mutable maps from
 *  immutable map implementations. Only method `empty` has
 *  to be redefined if the immutable map on which this mutable map is
 *  originally based is not empty. `empty` is supposed to
 *  return the representation of an empty map.
 *
 *  @author  Matthias Zenger
 *  @author  Martin Odersky
 *  @version 2.0, 01/01/2007
 *  @since   1
 */
@deprecated("Adaptors are inherently unreliable and prone to performance problems.", "2.11.0")
class ImmutableMapAdaptor[A, B](protected var imap: immutable.Map[A, B])
extends AbstractMap[A, B]
   with Map[A, B]
   with Serializable
{

  override def size: Int = imap.size

  def get(key: A): Option[B] = imap.get(key)

  override def isEmpty: Boolean = imap.isEmpty

  override def apply(key: A): B = imap.apply(key)

  override def contains(key: A): Boolean = imap.contains(key)

  override def isDefinedAt(key: A) = imap.isDefinedAt(key)

  override def keySet: scala.collection.Set[A] = imap.keySet

  override def keysIterator: Iterator[A] = imap.keysIterator

  @migration("`keys` returns Iterable[A] rather than Iterator[A].", "2.8.0")
  override def keys: scala.collection.Iterable[A] = imap.keys

  override def valuesIterator: Iterator[B] = imap.valuesIterator

  @migration("`values` returns Iterable[B] rather than Iterator[B].", "2.8.0")
  override def values: scala.collection.Iterable[B] = imap.values

  def iterator: Iterator[(A, B)] = imap.iterator

  override def toList: List[(A, B)] = imap.toList

  override def update(key: A, value: B): Unit = { imap = imap.updated(key, value) }

  def -= (key: A): this.type = { imap = imap - key; this }

  def += (kv: (A, B)): this.type = { imap = imap + kv; this }

  override def clear(): Unit = { imap = imap.empty }

  override def transform(f: (A, B) => B): this.type = { imap = imap.transform(f); this }

  override def retain(p: (A, B) => Boolean): this.type = {
    imap = imap.filter(xy => p(xy._1, xy._2))
    this
  }

  override def toString() = imap.toString()
}