如何使用订单号写入.txt文件

Question

我想把订单写入档案。例如，如果文件中的订单及其订单号为1，然后当用户添加另一个订单并点击保存时，订单将保存为.txt文件，作为该日期的订单号2。但是我的fileWriter写入了与订单号1相同的文件中的文件。请看看我的DaoImpl。谢谢。

private void writeOrder(LocalDate date) throws OrderPersistenceException, IOException {

    PrintWriter out;
    try {
        out = new PrintWriter(new FileWriter(getFilePath(date)));
    } catch (IOException ex) {
        throw new OrderPersistenceException("file");
    }

    List<Order> orderList = new ArrayList<>(orderMap.values());

    for (Order currentOrderList : orderList) {

        out.print(currentOrderList.getOrderNumber() + DELIMITER
                + currentOrderList.getCustomerName() + DELIMITER
                + currentOrderList.getState() + DELIMITER
                + currentOrderList.getTaxRate() + DELIMITER
                + currentOrderList.getProductType() + DELIMITER
                + currentOrderList.getArea() + DELIMITER
                + currentOrderList.getCostPerSquareFoot() + DELIMITER
                + currentOrderList.getLaborCostPerSquareFoot() + DELIMITER
                + currentOrderList.getMeterialCost() + DELIMITER
                + currentOrderList.getTotalTax() + DELIMITER
                + currentOrderList.getTotal());

        out.flush();
    }

    out.close();
}

public void saveWork(LocalDate date) throws OrderPersistenceException, IOException {
    writeOrder(date);

}

@Override
public Order addOrder(Order order) throws OrderPersistenceException {
    long orderNumber = ordernumberIncrease(order);
    Order newOrder = orderMap.put(orderNumber, order);

    return newOrder;

}

public Long ordernumberIncrease(Order order) {
    long orderNumber = orderNumInc++;
    order.setOrderNumber(orderNumber);
    return orderNumber;
}

Answer 1

您需要更新writeOrder方法：

在for循环使用out.println而不是out.print - 然后每个订单将从新行开始。