populating next right pointers in each node

public void (TreeLinkNode root) {
     if (root == null)
         return;
     List<TreeLinkNode> parents = new LinkedList<TreeLinkNode>();
     parents.add(root);
     while (parents.size() > 0) {
         for (int i = 0; i < parents.size() - 1; ++i) {
             parents.get(i).next = parents.get(i + 1);
         }
         List<TreeLinkNode> children = new LinkedList<TreeLinkNode>();
         for (TreeLinkNode node : parents) {
             if (node.left != null)
                 children.add(node.left);
             if (node.right != null)
                 children.add(node.right);
         }
         parents = children;
     }
 }