Where does xmlns:tns come from when using schemagen

Question

We are using schemagen to create an XSD from some annotated POJOs.

Here is our ant target

<target name="generate-xsd" depends="compile">
    <taskdef name="schemagen" classname="com.sun.tools.jxc.SchemaGenTask" 
                     classpathref="xjc.classpath"/>
    <schemagen srcdir="src" destdir="generated" includeantruntime="false">
        <include name="com/acme/exam/delivery/records/**"/>
        <schema namespace="http://www.acme.com/deliverylog" 
                            file="deliverylog.xsd"/>
        <schema namespace="" file="supplemental.xsd"/> 
    </schemagen>
</target>

This is generating

<xs:schema elementFormDefault="qualified" version="1.0" 
           targetNamespace="http://www.acme.com/deliverylog" 
           xmlns:tns="http://www.acme.com/deliverylog" 
           xmlns:xs="http://www.w3.org/2001/XMLSchema">

Where does the tns namespace come from and what does it signify?

Answer 1

That infomration comes from the package level annotation @XmlSchema which can be found in the package-info class. See below for an example.

package-info

@XmlSchema(
    namespace = "http://www.acme.com/deliverylo",
    elementFormDefault = XmlNsForm.QUALIFIED)
package example;

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

Sample XML

elementFormDefault specifies which elements should be namespace qualified (true = all, false = only global elements), and targetNamespace defines what the namespace is.

<foo xmlns="http://www.acme.com/deliverylog">
    <bar>Hello World</bar>
</foo>

For More Information

• http://blog.bdoughan.com/2010/08/jaxb-namespaces.html