Akka/Scala example source code file (WildcardTree.scala)

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

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

Akka tags/keywords

akka, hashmap, iterator, map, none, option, some, t, util, wildcardtree

The WildcardTree.scala Akka example source code

/**
 * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
 */

package akka.util

import annotation.tailrec
import collection.immutable.HashMap

private[akka] object WildcardTree {
  private val empty = new WildcardTree[Nothing]()
  def apply[T](): WildcardTree[T] = empty.asInstanceOf[WildcardTree[T]]
}
private[akka] final case class WildcardTree[T](data: Option[T] = None, children: Map[String, WildcardTree[T]] = HashMap[String, WildcardTree[T]]()) {

  def insert(elems: Iterator[String], d: T): WildcardTree[T] =
    if (!elems.hasNext) {
      copy(data = Some(d))
    } else {
      val e = elems.next()
      copy(children = children.updated(e, children.get(e).getOrElse(WildcardTree()).insert(elems, d)))
    }

  @tailrec final def find(elems: Iterator[String]): WildcardTree[T] =
    if (!elems.hasNext) this
    else {
      (children.get(elems.next()) orElse children.get("*")) match {
        case Some(branch) ⇒ branch.find(elems)
        case None         ⇒ WildcardTree()
      }
    }
}