how is read/parsing xml java STAX (mechanism)

Question

I try to understand how is working the mechanism of STAX java.

I have this xml file

<?xml version="1.0" encoding="UTF-8"?>
<orders>
    <order created='2012-07-12T15:29:33.000' ID='2343'>
        <product>
            <description>Sony 54.6" (Diag) Xbr Hx929 Internet Tv</description>
            <gtin>00027242816657</gtin>
            <price currency="USD">2999.99</price>
            <supplier>Sony</supplier>
        </product>
        <product>
            <description>Apple iPad 2 with Wi-Fi 16GB - iOS 5 - Black</description>
            <gtin>00885909464517</gtin>
            <price currency="USD">399.0</price>
            <supplier>Apple</supplier>
        </product>
        <product>
            <description>Sony NWZ-E464 8GB E Series Walkman Video MP3 Player Blue</description>
            <gtin>00027242831438</gtin>
            <price currency="USD">91.99</price>
            <supplier>Sony</supplier>
        </product>
    </order>
    <order created='2012-07-13T16:02:22.000' ID='2344'>
        <product>
            <description>Apple MacBook Air A 11.6" Mac OS X v10.7 Lion MacBook</description>
            <gtin>00885909464043</gtin>
            <price currency="USD">1149.0</price>
            <supplier>Apple</supplier>
        </product>
        <product>
            <description>Panasonic TC-L47E50 47" Smart TV Viera E50 Series LED HDTV</description>
            <gtin>00885170076471</gtin>
            <price currency="USD">999.99</price>
            <supplier>Panasonic</supplier>
        </product>
    </order>
</orders>

To mimic the behavior of this XML file we created an object with similar attributes

public class Product {

    private int orderID;
    private String createTime;
    private String description;
    private String gtin;
    private String price;
    private String supplier;
//getter and setter
}

With this I tried to read my xml file:

if (xmlEvent.isStartElement()){
               StartElement startElement = xmlEvent.asStartElement();
               if(startElement.getName().getLocalPart().equals("order")){
                   prod = new Product();
                   Attribute idAttr = startElement.getAttributeByName(new QName("ID"));
                   if(idAttr != null){
                       prod.setgetOrderID(Integer.parseInt(idAttr.getValue()));
                   }

                   Attribute orderTime = startElement.getAttributeByName(new QName("created"));
                   if(orderTime != null){
                       prod.setgetCreateTime(orderTime.getValue());
                   }




                   counter++;
                   //System.out.println("Obiect creat");
                 System.out.println(counter);
               }
               //set the other varibles from xml elements
               else if(startElement.getName().getLocalPart().equals("description")){
                   xmlEvent = xmlEventReader.nextEvent();
                   prod.setDescription(xmlEvent.asCharacters().getData());

               }else if(startElement.getName().getLocalPart().equals("gtin")){
                   xmlEvent = xmlEventReader.nextEvent();
                   prod.setGtin(xmlEvent.asCharacters().getData());

               }else if(startElement.getName().getLocalPart().equals("price")){
                   xmlEvent = xmlEventReader.nextEvent();
                   prod.setPrice(xmlEvent.asCharacters().getData());
               }else if(startElement.getName().getLocalPart().equals("supplier")){
                   xmlEvent = xmlEventReader.nextEvent();
                   prod.setSupplier(xmlEvent.asCharacters().getData());

               }

My problem is that, they are 5 products, but when I try to output them, are not the correct number. 1. If in: if(startElement.getName().getLocalPart().equals("orders")) the last parameter is "oders" in the output i see just one object (Panasonic TC-L47E50 47" Smart TV Viera E50 Series LED HDTV)

2. If last parameter is order in my output are 2 objects
3. if last parameter is "product" in my output I have all of them, 5.

What modification i need to do, for read entire information. My scope is to read the attribute "created" and "id" of order but with all my objects, not 1 or 2 Thanks !

Answer 1

If you're using JaxB , you don't neet to create classes either even parse XML file by yourself, that's why JaxB is made for! :)

---

Basic steps to read-write xml using JaxB / Unmarshaller and XSD

• Create a valid XSD file of your XML structure.
• Place it in your project folder.
• Right click XSD file and auto-generate JAXB classes .

• Use Unmarshaller to populate auto-generated classes from XML file:

   Unmarshaller u = jc.createUnmarshaller(); Orders os = (Orders) u.unmarshal( new FileInputStream( "orders.xml" ) ); 

That's it... JaxB will take care of classes, attributes, populate, write/read xml...