How to have custom namespace prefix

Question

I am new to JAXB. I am able to populate the XML. In my case I need my namespace prefix as

<set xmlns="www.google.com"
   xmlns:myName="www.google.com">

instead of

<set xmlns="www.google.com"
   xmlns:ns2="www.google.com">

I have used package-info class and also the @XmlType annotation. Do I need to add any variable to get the desired name for the second namespace like "xmlns:MyName' instead of "xmlns:ns2"?

Answer 1

If you are using EclipseLink JAXB (MOXy) as your JAXB provider or a recent version of the JAXB RI then you can do the following:

package-info

You can use the @XmlNs annotation on the xmlns property of the @XmlSchema annotation to specify the prefix for a namespace.

@XmlSchema(
    namespace="www.google.com",
    elementFormDefault = XmlNsForm.QUALIFIED,
    xmlns={
        @XmlNs(namespaceURI = "www.google.com", prefix = ""),
        @XmlNs(namespaceURI = "www.google.com", prefix = "myName"),
    })
package forum13817126;

import javax.xml.bind.annotation.*;

Java Model

Below is a simple Java model that I will use for this example.

package forum13817126;

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class Set {

}

Demo Code

The following demo code will create an instance of the domain model and marshal it to XML.

package forum13817126;

import javax.xml.bind.*;

public class Demo {

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

        Set set = new Set();

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

}

Output

Below is the output from running the demo code.

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<myName:set xmlns="www.google.com" xmlns:myName="www.google.com"/>

For More Information

• http://blog.bdoughan.com/2011/11/jaxb-and-namespace-prefixes.html

Answer 2

You need to add an xmlns property on the @XmlSchema annotation in package-info. Its value is an array of annotations giving suggested prefix mappings for the marshaller. While it is technically allowed to ignore these suggestions I find they are usually respected as long as there are no clashes (two different packages suggesting the same prefix for different URIs).