private static void treeInsert(char letter, String code)
  {
    TreeNode current = decodeTree;
    for (int i = 0; i < code.length(); i ++)
    {
        if (code.substring (i, i+1) == ".") 
            current = current.getLeft();
            if( current == null ) { current.setLeft(new TreeNode(new Character(' '), null, null)); }
        if (code.substring (i, i+1)== "-") 
            current = current.getRight();
            if( current == null ) { current.setRight(new TreeNode(new Character(' '), null, null)); }
    }
  }