scala.collection.mutable.DefaultMapModel.scala Maven / Gradle / Ivy
/*
* Scala (https://www.scala-lang.org)
*
* Copyright EPFL and Lightbend, Inc.
*
* Licensed under Apache License 2.0
* (http://www.apache.org/licenses/LICENSE-2.0).
*
* See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*/
package scala
package collection
package mutable
/** This class is used internally. It implements the mutable `Map`
* class in terms of three functions: `findEntry`, `addEntry`, and `entries`.
*
* @author Matthias Zenger
* @since 1
*/
@deprecated("this trait will be removed", "2.11.0")
trait DefaultMapModel[A, B] extends Map[A, B] {
type Entry = DefaultEntry[A, B]
protected def findEntry(key: A): Entry
protected def addEntry(e: Entry)
protected def entries: Iterator[Entry]
def get(key: A): Option[B] = {
val e = findEntry(key)
if (e == null) None
else Some(e.value)
}
override def put(key: A, value: B): Option[B] = {
val e = findEntry(key)
if (e == null) { addEntry(new Entry(key, value)); None }
else { val v = e.value; e.value = value; Some(v) }
}
def += (kv: (A, B)): this.type = { put(kv._1, kv._2); this }
def iterator = entries map {e => (e.key, e.value)}
}