Print a binary search tree

Greetings, here is my code:

import java.util.*;

class BinarySearchTreeSet
{

// Inner class defining a binary tree node

   private class TreeNode
   {
      private TreeNode left;
      private Comparable key;
      private TreeNode right;
   }

// instance variables

   private TreeNode root, parent, child;

// Constructor

   public BinarySearchTreeSet()
   {
      root = null;
   }

// Inserts a key into the set

   public void insert(Comparable key) throws DuplicateKey
   {
      TreeNode newNode;
      if (search(key))
         throw new DuplicateKey();
      newNode = new TreeNode();
      newNode.key = key;
      newNode.left = null;
      newNode.right = null;
      if (parent == null)
         root = newNode;
      else if (parent.key.compareTo(key) > 0)
         parent.left = newNode;
      else
         parent.right = newNode;
            System.out.println("The name " + key + " was added");
   }

// Removes a key from the set

   public void remove(Comparable key) throws NotFound
   {
      if (!search(key))
         throw new NotFound();
      if (child == root)
         root = deleteNode(root);
      else if (parent.left == child)
         parent.left = deleteNode(parent.left);
      else
         parent.right = deleteNode(parent.right);

        System.out.println("The name " + key + " was deleted");
   }

// Determines whether a key is in the set

   public boolean contains(Comparable key)
   {
      if (!search(key))
         return false;
      return true;
        }

// Private method that searches for a key

   private boolean search(Comparable key)
   {
      parent = null;
      child = root;
      while (child != null)
      {
         if (child.key.equals(key))
            return true;
         parent = child;
         if (child.key.compareTo(key) > 0)
            child = child.left;
         else
            child = child.right;
      }
      return false;
   }

// Private method that deletes a node

   private TreeNode deleteNode(TreeNode node)
   {
      TreeNode inorderSuccessor, successorsParent;

      if (node.right == null)
         return node.left; // 0-1 Child
      else if (node.left == null)
         return node.right; // 1 Child
      else
      { // 2 Children
         successorsParent = node.left;
         inorderSuccessor = successorsParent.right;
         if (inorderSuccessor == null)
         {
            node.left = successorsParent.left;
            node.key = successorsParent.key;
         }
           else
         {
            while (inorderSuccessor.right != null)
            {
               successorsParent = inorderSuccessor;
               inorderSuccessor = inorderSuccessor.right;
            }
            successorsParent.right = inorderSuccessor.left;
            node.key = inorderSuccessor.key;
         }
      }
   return node;
   }

    // begin print code
    // here is where I'm having problems
    public void printTree() {
        Queue<TreeNode> queue = new LinkedList<TreeNode>();
        queue.offer(root);
          System.out.println(root);
        while(!queue.isEmpty()) {
            TreeNode n = queue.poll();
            System.out.println(n.left + " <- " + n + " -> " +
n.right);
            if(n.left != null) queue.offer(n.left);
            if(n.right != null) queue.offer(n.right);
        }
    }
    // end print code
}

I get the following output when I call the printTree() method from my
driver:

BinarySearchTreeSet$TreeNode@1b67f74
// the following all on one line
BinarySearchTreeSet$TreeNode@69b332 <- BinarySearchTreeSet
$TreeNode@1b67f74 -> BinarySearchTreeSet$TreeNode@173a10f
// end of all on one line
null <- BinarySearchTreeSet$TreeNode@69b332 -> null
null <- BinarySearchTreeSet$TreeNode@173a10f -> null

This output is after adding "kevin", "billy", and "timmy" to the
tree. The add, contains, and remove methods all work fine. I just
need to get the tree printing to the console, and then I have to work
on file i/o.

Thanks in advance for any help...