Unmarshalling XML using JAXB

java, jaxb, xml

Solution

Below is one way that you could map your use case with a JAXB (JSR-222) implementation:

Items

We will use the following class for the root object and annotate it with `@XmlRootElement`. The `@XmlRootElement` annotation tells JAXB that this class should be instantiated if the root element in the document being unmarshalled is `items`, you can also specify a different name `@XmlRootElement(name="foo")`.

package forum11152046;

import java.util.List;
import javax.xml.bind.annotation.*;

@XmlRootElement
public class Items {

    private List<Item> items;

    @XmlElement(name="item")
    public List<Item> getItems() {
        return items;
    }

    public void setItems(List<Item> items) {
        this.items = items;
    }

}

Item

In this example I created a class where all the property names correspond directly to the names in the XML document. This means there aren't any annotations that need to be added. If you need to override the default name you can use an annotation such as `@XmlElement` to do so. I used the `@XmlElement` annotation to do this in the `Items` class for the `items` property.

package forum11152046;

public class Item {

    private int code;
    private String name;
    private int price;

    public int getCode() {
        return code;
    }

    public void setCode(int code) {
        this.code = code;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getPrice() {
        return price;
    }

    public void setPrice(int price) {
        this.price = price;
    }

}

Demo

package forum11152046;

import java.io.File;
import javax.xml.bind.*;

public class Demo {

    public static void main(String[] args) throws Exception {
        JAXBContext jc = JAXBContext.newInstance(Items.class);

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        File xml = new File("src/forum11152046/input.xml");
        Items items = (Items) unmarshaller.unmarshal(xml);

        Marshaller marshaller = jc.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
        marshaller.marshal(items, System.out);
    }

}

input.xml/Output

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<items>
    <item>
        <code>12000</code>
        <name>Samsung  620</name>
        <price>9999</price>
    </item>
    <item>
        <code>15000</code>
        <name>NOKIA</name>
        <price>19999</price>
    </item>
    <item>
        <code>18000</code>
        <name>HTC 620</name>
        <price>29999</price>
    </item>
</items>

Problem

Original source