java - 将对象编码为XML会导致添加重复的节点

我有一个需要编组到XML的对象。为此，我正在使用JAXB。创建了最终的XML文件，但是最后出现了重复的节点：

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<order>
    <supplier_id>suppliername</supplier_id>
    <store_name>storename</store_name>
    <order_id>1234567890</order_id>
    <order_item>
        <order_item_id>0987654321</order_item_id>
        <item_state>Shipped</item_state>
        <item_state_date>2012-12-27T14:40:00.000-05:00</item_state_date>
        <carrier_code>NA</carrier_code>
        <carrier_name>CarrierName</carrier_name>
        <shipping_method>Expedited</shipping_method>
        <tracking_number>348134987124872734817324</tracking_number>
        <backorder_replacement_sku_price>0.0</backorder_replacement_sku_price>
    </order_item>
    <order_item>
        <order_item_id>0987654321</order_item_id>
        <item_state>Shipped</item_state>
        <item_state_date>2012-12-27T14:40:00.000-05:00</item_state_date>
        <carrier_code>NA</carrier_code>
        <carrier_name>CarrierName</carrier_name>
        <shipping_method>Expedited</shipping_method>
        <tracking_number>348134987124872734817324</tracking_number>
        <backorder_replacement_sku_price>0.0</backorder_replacement_sku_price>
    </order_item>
    ....

我只需要第一个<order_item>节点，而后一个错误。

我的代码如下：

JAXBContext context = JAXBContext.newInstance(classname.class.getPackage().getName());
Marshaller marsheller = context.createMarshaller();

Order order = new Order();
OrderItem orderItem = new OrderItem();

...Business logic related to our ERP system...
//We start a loop here to iterate over search results. The goal is to have one XML file per search row returned. No knowledge of the ERP system is required.

for (SearchRow row : results.getSearchRowList().getSearchRow()) {
    //we capture our variables from the search results here and build our order and orderItem objects with them.

    order.setSupplierId("suppliername");
    order.setStoreName("storename");
    order.setOrderId(orderNumber);
    orderItem.setOrderItemId(orderItemId);
    orderItem.setItemState(StatusCodeType.SHIPPED);
    orderItem.setItemStateDate(date2);
    orderItem.setCarrierCode("NA");
    orderItem.setCarrierName(carrierName);
    orderItem.setShippingMethod(shippingMethod);
    orderItem.setTrackingNumber(trackingNumber);

    order.getOrderItem().add(orderItem);
    File f = new File("tempFiles/" + order.getOrderId() + ".xml");
    marsheller.marshal(order, f);
}

我以为问题是循环，但是如果从对象本身创建对象后记录所有变量，则仅显示orderItem结果，而不显示多个orderItems。

谁能指出我要离开的方向？

最佳答案

你要么需要


围绕循环每次迭代创建一个new Order()和new OrderItem()或
创建order.getOrderItem().add(orderItem);和Order实例后，立即将OrderItem移到循环外。


您当前的逻辑是每次循环时都将相同的OrderItem实例添加到列表中，因此第一次迭代将获得一个<order_item>元素，第二次迭代将获得两个相同的元素，第三次迭代将获得三个，等等