gistfile1.scala

import java.util.UUID

import scala.collection.mutable.{Map => MutableMap}

case class Terms(id:UUID, name:String) {
  val words=MutableMap[UUID, Word]()
}

case class Word(id:UUID, word:String, definition:String)

trait TermService {
  def getTerms(id:UUID):Terms
  def createTerms(name:String):Terms
}

object DefaultTermService extends TermService {
  val terms=MutableMap[UUID, Terms]()

  override def getTerms(id: UUID): Terms = {
    terms(id)
  }

  override def createTerms(name: String): Terms = {
    val collection=Terms(UUID.randomUUID(), name)
    terms += (collection.id -> collection)
    collection
  }
}

object Ontology {
  def main(args:Array[String]) = {
    val service=DefaultTermService
    val term=service createTerms("foo")
    val term2=service getTerms term.id
    println(term)
    println(term2)
    println(service.getTerms(UUID.randomUUID))
  }
}

// when run:
Terms(b11c898d-ac44-4c7a-a77e-43edd1f786da,foo)
Terms(b11c898d-ac44-4c7a-a77e-43edd1f786da,foo)
Exception in thread "main" java.util.NoSuchElementException: key not found: 68dc0cd1-9101-41dc-af0e-ab67a7704f92
	at scala.collection.MapLike$class.default(MapLike.scala:228)
	at scala.collection.AbstractMap.default(Map.scala:58)
	at scala.collection.mutable.HashMap.apply(HashMap.scala:64)
	at DefaultTermService$.getTerms(Ontology.scala:20)
	at Ontology$.main(Ontology.scala:37)
	at Ontology.main(Ontology.scala)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:483)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:134)

Process finished with exit code 1