Question

I have an object that I need to marshal to XML. To do this I am using JAXB. The resulting XML file is created, however I end up with duplicate nodes:

<?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>
    ....

I only require the first <order_item> node, and subsequent ones are there erroneously.

My code is as follows:

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);
}

I thought that the issue was the loop, but if I log all the variables after object creation from the objects themselves only show orderItem result and not multiple orderItems.

Can anyone point me in the direction where I am going off the tracks?

Answer 1

You either need to

• create a new Order() and new OrderItem() each iteration round the loop or
• move the order.getOrderItem().add(orderItem); to outside the loop immediately after you create the Order and OrderItem instances.

Your current logic is adding the same OrderItem instance to the list each time round the loop, so the first iteration you’ll get one <order_item> element, the second iteration you’ll get two identical ones, the third iteration three, etc.