Learning Scala

LinkedList.scala

class LinkedList(startNode:Node) {
    var lastNode = startNode
    def printList() =  {
        startNode.print()
    }
    def addNode(node:Node) = {
        this.lastNode.next = Some(node)
        node.last = Some(lastNode)
        this.lastNode = node
        
    }
}

class Node(var data:Option[String], var next:Option[Node], var last:Option[Node]) {
    def print() : Unit = {
        println(this.data.getOrElse("- No data -"))
        next match {
            case a: Some[_] => a.get.print()
            case other => println("Error!"); exit
        }
    }   
}

object Main{
    def main( args:Array[String] ) = {
        println("Running!")
        val n1 = new Node(Some("data"), None, None)
        val ll = new LinkedList(n1)
        val n2 = new Node(Some("data2"), None, None)
        val n3 = new Node(None, None, None)
        ll.addNode(n2)
        ll.addNode(n3)  
        ll.printList()
        println("Finished")
    } 
}