public Iterator<AbstractPage> childIterator(final boolean dirtyNodesOnly){
  if (dirtyNodesOnly) {
    return new DirtyChildIterator(this);
  }
 else {
    return new ChildIterator();
  }
}

public Iterator < AbstractPage > childIterator ( final boolean dirtyNodesOnly ) { if ( dirtyNodesOnly ) { return new DirtyChildIterator ( this ) ; } else { return new ChildIterator ( ) ; } }
iterator visits the direct child nodes in the external key ordering .
