Couldn't find JAX-B element for class java.lang.String error on REST method

[Mikael Gyth]

Hello. I have a problem i can't seem to figure out.

I have a set of REST Methods, this is two of them:

@GET
    @Path("{from}/{to}")
    @Produces({"application/xml", "application/json"})
    public List<Doerer> findRange(@PathParam("from") Integer from, @PathParam("to") Integer to) {
        return super.findRange(new int[]{from, to});
    }
    
    @GET
    @Path("/newer/{bruker}/{passord}/{version}")
    @Produces({"application/xml", "application/json"})
    public List<Doerer> findNewer(@PathParam("bruker") String bruker, @PathParam("passord") String passord, @PathParam("version") Double version){
        Query query = getEntityManager().createNativeQuery("SELECT * FROM Doerer d WHERE ID_Dor = ?");
        query.setParameter(1, 100);
        List<Doerer> rl = query.getResultList();
        return rl;
    }

The first one works just fine, the second one when I try to call it, I get this error:

type Status report

messageInternal Server Error

descriptionThe server encountered an internal error (Internal Server Error) that prevented it from fulfilling this request.

And in Glassfish I get:

SEVERE: Mapped exception to response: 500 (Internal Server Error)
javax.ws.rs.WebApplicationException: javax.xml.bind.JAXBException: class [Ljava.lang.Object; nor any of its super class is known to this context.
	at com.sun.jersey.core.provider.jaxb.AbstractListElementProvider.writeTo(AbstractListElementProvider.java:266)
	at com.sun.jersey.spi.container.ContainerResponse.write(ContainerResponse.java:306)
	at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1437)
	at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1349)
	at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1339)
	at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416)
	at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:537)
	at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:708)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:770)
	at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1550)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
	at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
	at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
	at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:331)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
	at com.sun.enterprise.v3.services.impl.ContainerMapper$AdapterCallable.call(ContainerMapper.java:317)
	at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
	at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:860)
	at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:757)
	at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1056)
	at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:229)
	at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
	at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
	at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
	at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
	at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
	at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
	at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
	at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
	at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
	at java.lang.Thread.run(Thread.java:722)
Caused by: javax.xml.bind.JAXBException: class [Ljava.lang.Object; nor any of its super class is known to this context.
	at com.sun.xml.bind.v2.runtime.JAXBContextImpl.getBeanInfo(JAXBContextImpl.java:588)
	at com.sun.xml.bind.v2.runtime.XMLSerializer.childAsRoot(XMLSerializer.java:482)
	at com.sun.xml.bind.v2.runtime.MarshallerImpl.write(MarshallerImpl.java:323)
	at com.sun.xml.bind.v2.runtime.MarshallerImpl.marshal(MarshallerImpl.java:178)
	at com.sun.jersey.json.impl.provider.entity.JSONListElementProvider.writeList(JSONListElementProvider.java:145)
	at com.sun.jersey.core.provider.jaxb.AbstractListElementProvider.writeTo(AbstractListElementProvider.java:264)
	... 32 more

INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String
INFO: Couldn't find JAX-B element for class java.lang.String

Can anyone please help me sort this out? Let me know if you need any aditional info.

Thanks in advance.

Edit: I know the parameters and the sql query doesn't make any sense in it's current state, I'v just been removing most of the query to get something i knew worked.

[Mikael Gyth]

Solution was to define the returning entity object in the namedQuery.

Query query = getEntityManager().createNativeQuery("SELECT d.* FROM Doerer d WHERE Version > ?", Doerer.class);