Question

I have some @javax.xml.bind.annotation.Xml… annotated classes here intended for a RESt web service. Jersey is setup in a spring managed web container and the web service is returning a well formatted xml. We use the maven-enunciate-plugin to document the web service and create the xsd to the returned xml documents. I now would like to use the documentation xsd file as a schemaLocation within the returned xml file so that the xml validation won’t complain about missing definions. How can I get the XML serialisation configured for this?

Answer 1

If I remember correctly, I had to do a few of things to get namespace identifiers properly written into my generated XML.

1) Created a JaxbFactory that configs and returns a custom marshaller (and unmarshaller, too, BTW). I’m omitting the getters/and unmarshalling setup below…

//constructor
public JaxbFactory() throws Exception {
    context = JAXBContext.newInstance(ResourceDto.class);

    // Setup the marshaller
    marshaller = context.createMarshaller();
    marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
    marshaller.setProperty(Marshaller.JAXB_SCHEMA_LOCATION, XmlMetadataConstants.XML_SCHEMA_LOCATION);  // this schema location is used in generating the schema-location property in the xml
}

2) That factory class isn’t “visible” to Jersey. To make it visible, I create a MarshallerProvider. That looks something like this:

@Provider
public class ResourceJaxbMarshallerProvider implements ContextResolver<Marshaller> {
// injected by Spring
private ResourceJaxbFactory ResourceJaxbFactory;
private ResourceStatusJaxbFactory ResourceStatusJaxbFactory;


/*
 * ----------------------------------------
 * Setters (for Spring injected properties)
 * ----------------------------------------
 */
public void setResourceJaxbFactory(ResourceJaxbFactory ResourceJaxbFactory) {
    this.ResourceJaxbFactory = ResourceJaxbFactory;
}

public void setResourceStatusJaxbFactory(ResourceStatusJaxbFactory ResourceStatusJaxbFactory) {
    this.ResourceStatusJaxbFactory = ResourceStatusJaxbFactory;
}

/*
 * ------------------------
 * Interface Implementation
 * ------------------------
 */
public Marshaller getContext(Class<?> type) {
    if (type == ResourceDto.class)
        return ResourceJaxbFactory.getMarshaller();
    else if (type == ResourceStatusDto.class)
        return ResourceStatusJaxbFactory.getMarshaller();
    else
        return null;
}       
}

I’ve got Jersey wired into Spring using the Jersey/Spring Servlet so any @Provider class that gets created by Spring is automatically recognized by Jersey. In my Spring applicationContext.xml all I have to do is instantiate the resource provider. It will, in turn, go grab the marshaller from the factory.

3) The other thing that I found critical was that I had to create a package-info.java file in the root package containing my resource. Looks like this:

/*
 * Note that this file is critical for ensuring that our ResourceDto object is
 * marshalled/unmarshalled with the correct namespace.  Without this, marshalled
 * classes produce XML files without a namespace identifier
 */
@XmlSchema(namespace = XmlMetadataConstants.XML_SCHEMA_NAMESPACE, elementFormDefault = XmlNsForm.QUALIFIED) 
package com.yourcompany.resource;

import javax.xml.bind.annotation.XmlNsForm;

---

At least I think that’s everything I needed to do, I can’t remember every single piece. I do remember that the package-info.java piece was the last critical cog that made it all come together.

Hope that helps. I spent wayyyy too much time digging for the info on all this. Jersey was seductively simple before I wanted it to do proper xml schema validation (and decent error reporting for schema-invalid input). Once I started down that road Jersey went from brain-dead easy to decently hard. The majority of that difficulty was sussing out all the details from the variety of posts online. Hopefully this will help get you farther, quicker. 🙂