Question

I want to unmarhal XML file into array of elements.

Example :

<root>
   <animal>
      <name>barack</name>
   </animal>
   <animal>
      <name>mitt</name>
   </animal>
</root>

I would like an array of Animal elements.

When I try

JAXBContext jaxb = JAXBContext.newInstance(Root.class);
Unmarshaller jaxbUnmarshaller = jaxb.createUnmarshaller();
Root r = (Root)jaxbUnmarshaller.unmarshal(is);
system.out.println(r.getAnimal.getName());

this display mitt, the last Animal.

I would like to do this :

Animal[] a = ....
// OR
ArrayList<Animal> = ...;

How can I do please ?

Answer 1

You could do the following:

Root

This example would work the same if the field was changed to List<Animal> or ArrayList<Animal>.

package forum13178824;

import javax.xml.bind.annotation.*;

@XmlRootElement
@XmlAccessorType(XmlAccessType.FIELD)
public class Root {

    @XmlElement(name="animal")
    private Animal[] animals;

}

Animal

package forum13178824;

import javax.xml.bind.annotation.*;

@XmlAccessorType(XmlAccessType.FIELD)
public class Animal {

    private String name;

}

Demo

package forum13178824;

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

public class Demo {

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

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        File xml = new File("src/forum13178824/input.xml");
        Root root = (Root) unmarshaller.unmarshal(xml);

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

}

input.xml/Output

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<root>
    <animal>
        <name>barack</name>
    </animal>
    <animal>
        <name>mitt</name>
    </animal>
</root>

For More Information

• http://blog.bdoughan.com/2010/09/jaxb-collection-properties.html
• http://blog.bdoughan.com/2011/06/using-jaxbs-xmlaccessortype-to.html