Create Tree from Preordered data

Question

Here is a quick summary of what I'm trying to do:
I have a file with formatted like this
Does it have legs?
Dog
Fish
and the resulting tree for it should look like this
     Does it have legs?
     Dog        Fishand I'm trying to write a function that takes in a Scanner object that should already be tied to the data file and create a tree from this data that is already listed in Preorder fashion. I know tha recurison is probably the best way to go about this but everything that I have written hasn't worked. Also, I cant really figure out a way to use recursion when the function is taking in a Scanner I dont know how it would work.
Any help would be greatly appreciated.
Here is what I have now:
     public BinaryTree<String> readTree(Scanner data)
          BinaryTree<String> temp = new BinaryTree<String>();
          temp.attachLeft(data.next());
          temp.attachRight(data.next());
          return temp;
     }I know this function wont go through the whoel file, but I've tried many loops but I cant figure out how to get it to work so I'm convinced that I need to figure out how to make it recursive
(yes I know that everything that can be done through recursion can be done with a loop)

Answer 1

@OP:
Here's how you could do it:
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
import java.util.Stack;
class Main {  
    public static void main(String[] args) throws FileNotFoundException {
        Scanner file = new Scanner(new File("data.txt"));
        BinTree tree = new BinTree(file);
        System.out.println(tree);
class BinTree  {
    private BinNode root;
    public BinTree(Scanner file) {
        // create the root (first line in the file)
        root = new BinNode(file.nextLine());
        // create a stack
        Stack<BinNode> stack = new Stack<BinNode>();
        // push the root on the stack: we need it to add nodes to the left and right of it
        stack.push(root);
        // call the insert method to build the tree
        insert(stack, file);
    private void insert(Stack<BinNode> stack, Scanner file) {
        IF 'file' has no more lines left
            stop this method
        END IF
        BinNode 'next' <- the next line in 'file'
        IF the left node of the last node on the 'stack' equals null
            the left child of last node of the stack <- 'next' (but leave the stack in tact)
        ESLE
            the right child of last node of the stack <- 'next' (remove the last node of the stack)
        END IF
        IF 'next' is a question
            push 'next' on the stack
        END IF
        recursively call the insert(...) method here
class BinNode {
    String data;
    BinNode right, left;
    public BinNode(String data) { this.data = data; }
    public String toString() { return this.data; }
}