private static void collect(final INaviOperandTreeNode currentNode,final List<INaviOperandTreeNode> nodes){
  nodes.add(currentNode);
  for (  final INaviOperandTreeNode child : currentNode.getChildren()) {
    collect(child,nodes);
  }
}

private static void collect ( final INaviOperandTreeNode currentNode , final List < INaviOperandTreeNode > nodes ) { nodes . add ( currentNode ) ; for ( final INaviOperandTreeNode child : currentNode . getChildren ( ) ) { collect ( child , nodes ) ; } }
collects all nodes of an operand tree .
