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javaxml-serializationxml-namespacesxstream

How to add an XML namespace (xmlns) when serializing an object to XML

I'm serializing Objects to XML with the help of XStream. How do I tell XStream to insert an xmlns to the XML output of my object?

As an example, I have this simple object I want to serialize:

@XStreamAlias(value="domain")
public class Domain
{
    @XStreamAsAttribute
    private String type;

    private String os;

    (...)
}

How do I achieve exactly the following output with XStream?

<domain type="kvm" xmlns:qemu="http://libvirt.org/schemas/domain/qemu/1.0">
  <os>linux</os>
</domain>
Solution

  • Alternatively, this use case could be handled quite easily with a JAXB implementation (Metro, EclipseLink MOXy, Apache JaxMe, etc):

    Domain

    package com.example;

import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class Domain
{
    private String type;
    private String os;

    @XmlAttribute
    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    }

    public String getOs() {
        return os;
    }

    public void setOs(String os) {
        this.os = os;
    }

}

    package-info

    @XmlSchema(xmlns={
        @XmlNs(
            prefix="qemu", 
            namespaceURI="http://libvirt.org/schemas/domain/qemu/1.0")
})
package com.example;

import javax.xml.bind.annotation.XmlNs;
import javax.xml.bind.annotation.XmlSchema;

    Demo

    package com.example;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;

public class Demo {

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

        Domain domain = new Domain();
        domain.setType("kvm");
        domain.setOs("linux");

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


}

    Output

    <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<domain xmlns:qemu="http://libvirt.org/schemas/domain/qemu/1.0" type="kvm">
    <os>linux</os>
</domain>

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