CODEWITHSUNDEEP
javajsonspringjaxbjax-rs
James Robinson
James Robinson

Reputation: 1263

JSON Jersey Auto serialization Wrapper Problems

I have a POJO

public class Graph {
    public int v;
    public int e;
}

and a very simple service

@Service("graph-service#default")
public class DefaultGraphService implements GraphService {
    public Response createGraph(Graph graph) {
        return Response.ok().build();
    }
}

which implements a very simple interface

@Path( "graph-service" )
public interface GraphService {

    @Path( "create-graph" )
    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    public Response createGraph(Graph graph);
}

I have a simple spring-context.xml set up as follows

<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:context="http://www.springframework.org/schema/context"
   xmlns:jaxrs="http://cxf.apache.org/jaxrs"
   xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
       http://www.springframework.org/schema/context 
       http://www.springframework.org/schema/context/spring-context-3.0.xsd
       http://cxf.apache.org/jaxrs
       http://cxf.apache.org/schemas/jaxrs.xsd">

    <import resource="classpath:META-INF/cxf/cxf.xml"/>
    <import resource="classpath:META-INF/cxf/cxf-servlet.xml"/>

    <context:annotation-config/>
    <context:component-scan base-package="me.jamesphiliprobinson.graphs"/>

    <jaxrs:server id="testServices" address="/testServices">
        <jaxrs:serviceBeans>
            <ref bean="graph-service#default"/>
        </jaxrs:serviceBeans>
        <jaxrs:providers>
            <ref bean="jsonProvider"/>
        </jaxrs:providers>
    </jaxrs:server>
    <bean id="jsonProvider" class="org.codehaus.jackson.jaxrs.JacksonJsonProvider" />
</beans>

If I spin the service up in tomcat it works fine can I can curl an object like

{"v":2,"e":1}

Without any difficulty. However, if I run this test

@Test
public void testCreateGraph() {
    UncertaintyGraphService service =
            JAXRSClientFactory.create( "http://localhost:" + port + "/" + getRestServicesPath() + "/testServices/",
                                       GraphService.class );
    Graph graph = new Graph();
    graph.e = 1;
    graph.v = 2;
    Response result = service.createGraph(graph);
    assertNotNull(result);
}

Then it fails as there is 

No message body writer has been found for class : class me.jamesphiliprobinson.graphs.Graph, ContentType : application/json

If I add an 

@XmlRootElement

to the POJO then the service serializes the graph object but seems to send

{"graph":{"e":1,"v",2}}

Instead which I can see making sense but the deserialization seems to still expect

{"e":1,"v":2}

As I get the error 

WARNING: WebApplicationException has been caught : Unrecognized field "graph" (Class me.jamesphiliprobinson.graphs.Graph), not marked as ignorable

I'm surely missing something incredibly simple. I would prefer for the items to serialise to

{"v":2,"e":1}

But if they will deserialise correctly I can live with a root element. i.e.

{"graph":{"v":2,"e":1}}

Upvotes: 1

Views: 215

Answers (1)

Paul Samsotha
Paul Samsotha

Reputation: 209022

See where you are registering the JacksonJsonProvider on the server?

<bean id="jsonProvider" class="org.codehaus.jackson.jaxrs.JacksonJsonProvider" />

This is to handle JSON (de)serizalization to/from POJO on the server side. But the client needs the same support. You can use the overloaded

to register the provider on the client side. Just add the JacksonJsonProvider to the List of providers.

JAXRSClientFactory.create(baseUri, Service.class, Arrays.asList(new JacksonJsonProvider())

Upvotes: 1

Related Questions