Question

I am having trouble customizing my JAXB Marshaller. I have my marshaller code:

public void marshaller(AddressMap addMap, File file) {
    try {
        JAXBContext jaxbContext = JAXBContext.newInstance(AddressMap.class);
        Marshaller jaxbMarshaller = jaxbContext.createMarshaller();

        jaxbMarshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
        jaxbMarshaller.marshal(addMap, System.out);

    } catch (JAXBException e) {
        e.printStackTrace();
    }
}

The output looks like this:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ObjectMap>
 <Prop> Indiana</Prop>
 <Prop1>39.0</Prop1>
 <Prop2>-85.0</Prop2>
 <Prop3> United States</Prop3>
 <Prop4> Hueseman Rd</Prop4>
 <Prop5> 8540-8704</Prop5>
 <Prop6> 47001</Prop6>
</ObjectMap>

Instead, I need it to look like this:

<bean class="classname">
    <property name="PropName" value="object value" />
    <property name="PropName1" value="object value" />
    <property name="PropName2" value="object value" />
    <property name="PropName3" value="object value" />
    <property name="PropName4" value="object value" />
    <property name="PropName5" value="object value" />
    <property name="PropName6" value="object value" />
</bean>

Answer 1

Note: I’m the EclipseLink JAXB (MOXy) lead and a member of the JAXB (JSR-222) expert group.

You could use MOXy’s @XmlDesciminatorNode and @XmlPath extensions to map this use case. Below is an example based on what I assume your object model looks like.

ObjectMap

The @XmlDescriminatorNode annotation allows you to specify that you want a specific XML attribute to serve as the inheritance indicator.

package forum13884782;

import javax.xml.bind.annotation.XmlRootElement;

import org.eclipse.persistence.oxm.annotations.XmlDiscriminatorNode;

@XmlRootElement(name="bean")
@XmlDiscriminatorNode("@class")
public class ObjectMap {

}

AddressMap

The @XmlDescriminatorValue annotation is used to specify the value on the descriminator node that relates to the instance class. In this class we also use the @XmlPath annotation to indicate which property element we wish to map to based on the value of its name attribute.

package forum13884782;

import javax.xml.bind.annotation.*;

import org.eclipse.persistence.oxm.annotations.*;

@XmlRootElement(name="bean")
@XmlAccessorType(XmlAccessType.FIELD)
@XmlDiscriminatorValue("AddressMap")
public class AddressMap extends ObjectMap {

    @XmlPath("property[@name='PropName']/@value")
    String prop;

    @XmlPath("property[@name='PropName1']/@value")
    String prop1;

    @XmlPath("property[@name='PropName2']/@value")
    String prop2;

    @XmlPath("property[@name='PropName3']/@value")
    String prop3;

    @XmlPath("property[@name='PropName4']/@value")
    String prop4;

    @XmlPath("property[@name='PropName5']/@value")
    String prop5;

    @XmlPath("property[@name='PropName6']/@value")
    String prop6;

}

jaxb.properties

To specify MOXy as your JAXB provider you need to include a file called jaxb.properties in the same package as your domain model with the following entry.

javax.xml.bind.context.factory=org.eclipse.persistence.jaxb.JAXBContextFactory

Demo

The following demo code will convert the XML message to an instance of AddressMap and then back to XML.

package forum13884782;

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

public class Demo {

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

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        File xml = new File("src/forum13884782/input.xml");
        AddressMap addressMap = (AddressMap) unmarshaller.unmarshal(xml);

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

}

input.xml/Output

<bean class="AddressMap">
    <property name="PropName" value="Indiana" />
    <property name="PropName1" value="39.0" />
    <property name="PropName2" value="-85.0" />
    <property name="PropName3" value="United States" />
    <property name="PropName4" value="Hueseman Rd" />
    <property name="PropName5" value="8540-8704" />
    <property name="PropName6" value="47001" />
</bean>

For More Information

• http://blog.bdoughan.com/2010/11/jaxb-and-inheritance-moxy-extension.html
• http://blog.bdoughan.com/2011/03/map-to-element-based-on-attribute-value.html
• http://blog.bdoughan.com/2011/05/specifying-eclipselink-moxy-as-your.html