How can I configure an Engine to connect my custom MediaType with DTO class?

[Krasnyanskiy]

Hi guys!

I'm stuck with Restlet Engine configuration. Let me show my simple code

Engine.getInstance().getRegisteredClients().clear();
Engine.getInstance().getRegisteredClients().add(new HttpClientHelper(null));
Engine.getInstance().getRegisteredConverters().add(new JacksonConverter());

ClientResource resource = new ClientResource(path);
ChallengeScheme scheme = ChallengeScheme.HTTP_BASIC;
ChallengeResponse auth = new ChallengeResponse(scheme, "user", "secret");

resource.setChallengeResponse(auth);
resource.getClientInfo().getAcceptedMediaTypes().add(new Preference<MediaType>(MediaType.register("application/repo.input+xml", "Type of DTO")));
ClientControl entity = resource.get(ClientControl.class);
System.out.println(entity);

But I'm get null entity and this

WARNING: Unable to find a converter for this representation : [application/repo.input+xml]

How can I retrieve an entity regarding to the proper MediaType?

Thanks,
Alex

[Krasnyanskiy]

By the way, my DTO ClientControl use JAXB notations. I'm not sure is Restlet supports JAXB architecture.

[Krasnyanskiy]

And no response...

[jlouvel]

JAXB is supported, did you try org.restlet.ext.jaxb.JaxbConverter?

[Krasnyanskiy]

Not yet. And thanks for your answer :)

[Krasnyanskiy]

I added

Engine.getInstance().getRegisteredConverters().add(new JaxbConverter());

and tried to

JaxbRepresentation<ClientControl> result = new JaxbRepresentation<ClientControl>(resource.get(), ClientControl.class);
ClientControl controlEntity = (ClientControl) result.getContext().createUnmarshaller().unmarshal(new StringReader(entity.getText()));

and got this exception

Exception in thread "main" javax.xml.bind.JAXBException: Provider com.sun.xml.bind.v2.ContextFactory could not be instantiated: javax.xml.bind.JAXBException: "com.example.resources" doesnt contain ObjectFactory.class or jaxb.index
 - with linked exception:
[javax.xml.bind.JAXBException: "com.example.resources" doesnt contain ObjectFactory.class or jaxb.index]
    at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:146)
    at javax.xml.bind.ContextFinder.find(ContextFinder.java:334)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:431)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:394)
    at org.restlet.ext.jaxb.JaxbRepresentation.getContext(JaxbRepresentation.java:103)
    at org.restlet.ext.jaxb.JaxbRepresentation.getContext(JaxbRepresentation.java:360)

[jlouvel]

This is a JAXB specific error. Let me know if you manage to fix it.

[Krasnyanskiy]

I found some ugly solution. First we need to create an ObjectFactory class. We need it for binding compiling.

@XmlRegistry
public class ObjectFactory {
    ClientControl createClientControl(){
        return new ClientControl();
    }
}

Than the final code will be like that

JAXBContext context = JAXBContext.newInstance(ObjectFactory.class.getPackage().getName(), ObjectFactory.class.getClassLoader());
Unmarshaller unmarshaller = context.createUnmarshaller();
ClientControl entity = (ClientControl) unmarshaller.unmarshal(new StringReader(resource.get().getText()));

Need to check it with Android platform. Frankly I'm not sure is it ok with all this mobile stuff.

[jlouvel]

You should be able to simplify this, see this test code:
https://github.com/restlet/restlet-framework-java/tree/master/modules/org.restlet.test/src/org/restlet/test/ext/jaxb

[Krasnyanskiy]

Oh, many thanks. I didn't noticed that before. Will check.

[Krasnyanskiy]

It's weird, but simplifying code as your suggested (in the test) doesn't work for me. Furthermore my verbose code

JAXBContext context = JAXBContext.newInstance(ObjectFactory.class.getPackage().getName(), ObjectFactory.class.getClassLoader());
Unmarshaller unmarshaller = context.createUnmarshaller();
ClientControl entity = (ClientControl) unmarshaller.unmarshal(new StringReader(resource.get().getText()));

works fine and returns a proper entity. But this one

ConverterService service = new ConverterService();
JaxbRepresentation<ClientControl> clientControl = new JaxbRepresentation<>(new MediaType("application", "repo.input+xml"), new ClientControl());
ClientControl clientControlEntity = service.toObject(clientControl, ClientControl.class, resource);

returns entity with null fields (not proper). In the second example I don't use ObjectFactory class.