public static void main(String[] args) throws Exception {
        Scanner scanner =new Scanner(new File("/home/lixinyu/workspace/Lisp/src/test.txt"));
//        scanner.readFileToString(filename);
        Token token;
//        scanner.readFileToString(filename);
        while(true)
        {
            try
            {
                token = scanner.getNextToken();

            }catch(Exception e)
            {
                token = null;
            }
            if(token.type != TokenType.FILEEOF)
            {
                switch(token.type)
                {
                case TokenType.DOT:
                {
                    //System.out.println("Dot");
                    System.out.print(". ");
                    break;
                }
                case TokenType.INT:
                {
                    //System.out.println("Integer " + token.Value);
                    System.out.print(token.value);
                    break;
                }
                case TokenType.ID:
                {
                    //System.out.println("ID " + token.Value);
                    System.out.print(token.value);
                    break;
                }
                case TokenType.LPAREN:
                {
                    //System.out.println("LPAREN");
                    System.out.print("(");
                    break;
                }
                case TokenType.RPAREN:
                {
                    //System.out.println("RPAREN");
                    System.out.print(")");
                    break;
                }               
                }
            }
            else
                break;
        }
    }