XmlRootElement annotation and marshalling error

[Mickael Marrache]

Hi,

I'm working on a REST web service. In my WADL, I've defined only one resource B 
where I define multiple possible operations on B (GET, PUT, DELETE...). I also 
import in my WADL, a XML schema where B is declared using a complexType but 
without defining a root element. After generating my code using WADL2Java 
plugin, I get the resource interface of B and the classes generated from my 
schema. As expected, the class B (corresponding to the complexType B) is not 
annotated with @XmlRootElement. So, when I call the GET method on a given 
resource of type B, I get an error since the resource can't be marshaled.

I've looked on the web for a solution and I've found this blog 
http://blog.bdoughan.com/2012/07/jaxb-and-root-elements.html. It seems that the 
solution is to create JAXBElement's that wrap my B instances. But, I don't 
understand how it works in the context of a REST service.

Here's my WADL:

<?xml version="1.0"?>
<application xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
            xsi:schemaLocation="http://wadl.dev.java.net/2009/02 
http://www.w3.org/Submission/wadl/wadl.xsd";
            xmlns:xsd="http://www.w3.org/2001/XMLSchema"; 
xmlns="http://wadl.dev.java.net/2009/02";
            xmlns:srvcb="com:mycomp:service:base">

            <grammars>
                        <schema xmlns="http://www.w3.org/2001/XMLSchema";
                                   targetNamespace="com:mycomp:service:rest">
                                   <import namespace="com:mycomp:service:base"
                                               schemaLocation="schema.xsd" />
                        </schema>
            </grammars>

            <resources base="REPLACE_WITH_THE_BASE_URL">
                        <resource id="BResource" path="/B/{id}">
                                   <method id="getB" name="GET">
                                               <request>
                                                           <param name="id" 
style="template" type="xsd:string" />
                                               </request>
                                               <response status="200">
                                                           <representation 
mediaType="application/xml" element="srvcb:BType" />
                                               </response>
                                   </method>
                        </resource>
            </resources>
</application>

I get the following interface:

@Path("/B/{id}")
public interface BResource {

    @GET
    @Produces("application/xml")
    BType getB(@PathParam("id") String id);

}

I don't understand how can I create a JAXBElement that wraps my BType's 
instance and also, how all of this works in this context. The getB method 
returns an instance of BType, not a JAXBElement instance. I'm confused.

Thanks,
Mickael