Question

I wonder if anyone can help, I have the following xml file, the problem is I can not see the third node ‘food’. I have created the files using JAXB there are four files have been created ObjectFactory, Breakfast-menu, foodType and food. I can get to foodType from Breakfast-menu and see the name(fresh and frozen) but not ‘food’ and it’s content. can some please give some ideas.
thanks

<Breakfast-menu>
    <foodType>
        <name>fresh</name>
        <food name="Milk">
            <price>2</price>
        </food>
        <food name="Pears">
            <price>3</price>
        </food>
        <food name="Apples">
            <price>1</price>
        </food>
    </foodType>
    <foodType>
        <name>frozen</name>
        <food name="Fish">
            <price>2</price>
        </food>
        <food name="chips">
            <price>1</price>
        </food>
    </foodType>
</Breakfast-menu>

Java

JAXBContext jaxbContext = JAXBContext.newInstance("food");
              Unmarshaller u = jaxbContext.createUnmarshaller();

              BreakfastMenu bM = (BreakfastMenu) u.unmarshal( 
                      new FileInputStream( "C:\\Users\\food.xml" ));
              List<FoodType> tType = bM.getFoodType();                
              for (FoodType tT : tType) {
                System.out.println("\t" + tT.getFood());

              }

Answer 1

Since this use case has a very simple XML document I would recommend starting from Java objects.

BreakfastMenu

JAXB (JSR-222) is configuration by exception so you only need to add annotations where you want the binding to differ from the default (see: http://blog.bdoughan.com/2012/07/jaxb-no-annotations-required.html).

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

@XmlRootElement(name="Breakfast-menu")
public class BreakfastMenu {

    private List<FoodType> foodType;

    public List<FoodType> getFoodType() {
        return foodType;
    }

    public void setFoodType(List<FoodType> foodType) {
        this.foodType = foodType;
    }

}

FoodType

By default the mappings are based on the public properties, but we can change JAXB to use fields with the @XmlAccessorType(XmlAccessType.FIELD) annotation (see: http://blog.bdoughan.com/2011/06/using-jaxbs-xmlaccessortype-to.html).

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

@XmlAccessorType(XmlAccessType.FIELD)
public class FoodType {

    private String name;

    @XmlElement(name="food")
    private List<Food> foods;

}

Food

import javax.xml.bind.annotation.*;

@XmlAccessorType(XmlAccessType.FIELD)
public class Food {

    @XmlAttribute
    private String name;

    private int price;

}

Demo

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

public class Demo {

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

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        File xml = new File("src/forum14751166/input.xml");
        BreakfastMenu bm = (BreakfastMenu) unmarshaller.unmarshal(xml);

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

}