public class AccountDao extends JdbcDaoSupport {

    public Account getAccount(String accountId) {
        List<Account> list = null;

        list = getJdbcTemplate().query("select account_id,balance from tb_account where account_id=?",
                new Object[] { accountId }, new RowMapper<Account>() {

                    @Override
                    public Account mapRow(ResultSet rs, int rowNum) throws SQLException {
                        Account acc = new Account();
                        acc.setAccountId(rs.getString("account_id"));
                        acc.setBalance(rs.getInt("balance"));
                        return acc;
                    }
                });
        if (list.size() > 0) {
            return list.get(0);
        } else {
            return null;
        }
    }

    public int updateAccount(String accountId, int balance) {
        int ret = getJdbcTemplate().update("update tb_account set balance = ? where account_id =?",
                new Object[] { balance, accountId });
        return ret;
    }
}