How to set namespace aware to false?

Question

I'm trying to parse some XML with EclipseLink MOXy, and it's failing on the line with the xsi attribute. If I remove this, it parses fine. However, I've got 100GiB of XML to wade through and changing the source files is not an option.

It's been suggested that if I can set XmlParser.setNamespaceAware(false) then it should work - but I've got no idea how to configure this, without breaking right into the guts of MOXy.

<record>
<header>
    <!-- citation-id: 14404534; type: journal_article; -->
    <identifier>info:doi/10.1007/s10973-004-0435-2</identifier>
    <datestamp>2009-04-28</datestamp>
    <setSpec>J</setSpec>
    <setSpec>J:1007</setSpec>
    <setSpec>J:1007:2777</setSpec>
</header>
<metadata>
    <crossref xmlns="http://www.crossref.org/xschema/1.0"
        xsi:schemaLocation="http://www.crossref.org/xschema/1.0 http://www.crossref.org/schema/unixref1.0.xsd">
        <journal>
            <journal_metadata language="en">
[...]

The exception I get when the xsi: prefix is present is:

org.springframework.oxm.UnmarshallingFailureException: JAXB unmarshalling exception; nested exception is javax.xml.bind.UnmarshalException
 - with linked exception:
[Exception [EclipseLink-25004] (Eclipse Persistence Services - 2.4.0.v20120608-r11652): org.eclipse.persistence.exceptions.XMLMarshalException
Exception Description: An error occurred unmarshalling the document
Internal Exception: javax.xml.stream.XMLStreamException: ParseError at [row,col]:[13,107]
Message: http://www.w3.org/TR/1999/REC-xml-names-19990114#AttributePrefixUnbound?crossref&xsi:schemaLocation&xsi]

Solution 1

There currently isn't an option in EclipseLink JAXB (MOXy) to tell it to ignore namespaces. But there is an approach you can use by leveraging a StAX parser.

Demo

You can create a StAX XMLStreamReader on the XML input that is not namespace aware and then have MOXy unmarshal from that.

package forum13416681;

import javax.xml.bind.*;
import javax.xml.stream.*;
import javax.xml.transform.stream.StreamSource;

public class Demo {

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

        XMLInputFactory xif = XMLInputFactory.newFactory();
        xif.setProperty(XMLInputFactory.IS_NAMESPACE_AWARE, false);
        StreamSource source = new StreamSource("src/forum13416681/input.xml");
        XMLStreamReader xsr = xif.createXMLStreamReader(source);

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        Foo root = (Foo) unmarshaller.unmarshal(xsr);

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

}

Java Model (Foo)

package forum13416681;

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class Foo {

    private String bar;

    public String getBar() {
        return bar;
    }

    public void setBar(String bar) {
        this.bar = bar;
    }

}

Input (input.xml)

Below is a simplified version of the XML from your question. Note that this XML is not properly namespace qualified since it is missing the namespace declaration for the xsi prefix.

<?xml version="1.0" encoding="UTF-8"?>
<foo xsi:schemaLocation="http://www.crossref.org/xschema/1.0 http://www.crossref.org/schema/unixref1.0.xsd">
    <bar>Hello World</bar>
</foo>

Output

Below is the output from running the demo code.

<?xml version="1.0" encoding="UTF-8"?>
<foo>
   <bar>Hello World</bar>
</foo>

Solution 2

Rather than disabling namespace awareness altogether, you may be able to use a StAX-implementation-specific mechanism to declare the xsi prefix in advance, then parse with namespaces enabled. For example, with Woodstox you can say:

import javax.xml.bind.*;
import javax.xml.stream.*;
import javax.xml.transform.stream.StreamSource;
import com.ctc.wstx.sr.BasicStreamReader;

public class Demo {

    public static void main(String[] args) throws Exception {
        JAXBContext jc = JAXBContext.newInstance("com.example");

        XMLInputFactory xif = XMLInputFactory.newFactory();
        StreamSource source = new StreamSource("input.xml");
        XMLStreamReader xsr = xif.createXMLStreamReader(source);
        ((BasicStreamReader)xsr).getInputElementStack().addNsBinding(
               "xsi", "http://www.w3.org/2001/XMLSchema-instance");

and then create the unmarshaller and unmarshal the xsr as in Blaise's answer. While this obviously ties you to one specific StAX implementation, it means that you don't have to modify your existing JAXB model classes if they expect the <crossref> element and its children to be in the http://www.crossref.org/xschema/1.0 namespace.