在Scala中的地图上存储迭代器

Question

I need to store an iterator on a Map to implement a traversal of a trie. In Java I did:

class Node {

  HashMap<Character, Node> children = new HashMap<>();
  Iterator<Character> i = children.keySet().iterator();

  public boolean hasNext() {
    return i.hasNext();
  }

  public CharNode next() {
    Character letter = i.next();
    return new CharNode(letter, children.get(letter));
  }
...

The reason I am doing this is that I use a queue to traverse the trie, and the iterators maintain the state of the traversal.

In Scala, I couldn't figure out how to create the corresponding iterator though, unless I fall back on Java util.Iterator, and Java util.Map. Is there a more idiomatic way to do this in Scala?

Answer 1

HashMap in Scala also supports iterator()

http://www.scala-lang.org/api/current/#scala.collection.immutable.HashMap

http://www.scala-lang.org/api/current/#scala.collection.Iterator