Resteasy and Spring - howto register javax.xml.bind.ValidationEventHandler

[Maciej Miklas]

Hi,

I've registered custom XML Mappers with javax.xml.bind.annotation.adapters.XmlAdapter. Such mapper can throw exception - the problem is, that resteasy ignores such exception. I would like to break REST call and return error to the client.

To do that I need to register javax.xml.bind.ValidationEventHandler on Marschaller/Unmarschaller.

Does anyone know how to do that with Jboss resteasy? I am using resteasy servlet to process requests, this servlet creates Marschaller/Unmarschaller somwhere inside......

Thanks,
Maciek

[Maciej Miklas]

This is the soluton (Spring+resteasy):

@Component
@Provider
@Consumes({ MediaType.APPLICATION_XML })
public class XmlMessageBodyReader implements MessageBodyReader<Object> {

    /** XML parsers */
    @Context
    protected Providers providers;

    /** Default event handler recognizes XML parsing as error and not as warning */
    private ValidationEventHandler errorhandler = new DefaultValidationEventHandler();

    protected JAXBContextFinder getFinder(MediaType type) {
        ContextResolver<JAXBContextFinder> resolver = providers.getContextResolver(JAXBContextFinder.class, type);
        if (resolver == null) {
            throw new IllegalArgumentException("Unable to find ContextResolver for media type: " + type);
        }
        return resolver.getContext(null);
    }

    /** {@inheritDoc} */
    @Override
    public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
        return true;
    }

    /**
     * {@inheritDoc}
     * <p>
     * Standard JAXB unmarshaller with custom error handler- {@link #errorhandler}
     */
    @Override
    public Object readFrom(Class<Object> type, Type genericType, Annotation[] annotations, MediaType mediaType,
            MultivaluedMap<String, String> httpHeaders, InputStream entityStream) throws IOException, WebApplicationException {

        if (entityStream == null) {
            return null;
        }
        try {
            JAXBContext ctx = getFinder(mediaType).findCacheContext(mediaType, annotations, type);
            Unmarshaller unmarshaller = ctx.createUnmarshaller();

            AbstractJAXBProvider.decorateUnmarshaller(type, annotations, mediaType, unmarshaller);

            unmarshaller.setEventHandler(errorhandler);
            Object parsedObj = unmarshaller.unmarshal(entityStream);
            return parsedObj;
        } catch (JAXBException e) {
            throw new JAXBMarshalException(e);
        }
    }
}