Thread: [Resteasy-users] Confused on handling response containing collections in json

Status: Pre-Alpha

Brought to you by: asoldano, patriot1burke, rmcdonough

resteasy-users

[Resteasy-users] Confused on handling response containing collections in json

From: Mike M. <Mik...@jd...> - 2013-09-04 19:39:38

We are building a restful api, using 2.3.5 (although I don't think the release level matters) and I am a bit confused on response handling within RestEasy:

Right or wrong, we made most of our resource methods return Response, using the GenericEntity when we wanted to return a collection of objects.    Testing up to now was in Chrome Advanced Rest Client.  We have our beans JAXB annotated and the resource 'produces' both application/xml and application/json.  For example:


@GET
       @Produces({"application/json", "application/xml"})
       public Response find(@Context UriInfo uriInfo)
       {
              setupQueryParms(uriInfo.getQueryParameters());
              List<Customer> custList = null;
              try {
                     custList = listAllPaginated();
              } catch (FinderException e) {
                     Log.getInstance().error("FinderException caught :", e );
                     throwException(Response.Status.NOT_FOUND, "Error searching customers");
              }

              GenericEntity<List<Customer>> entity = new GenericEntity<List<Customer>>(custList) {};
              return Response.ok(entity).build();
       }

Now, as part of writing JUnit test cases, I wanted to take the response I get back and put it back to object form so that I can then do a set of asserts against the object or list of objects returned.   I downloaded Jackson version 1.9.11 and tried to serialize/marshal the json back to object form but keep getting the following error:

Exception in thread "main" org.codehaus.jackson.map.exc.UnrecognizedPropertyException: Unrecognized field "Customer" (Class com.jda.portfolio.api.rest.base.Customer), not marked as ignorable
at [Source: C:\PPOSDevelopment\Trunk\API\REST\Server\response.json; line: 1, column: 15] (through reference chain: com.jda.portfolio.api.rest.base.Customer["Customer"])



Is there a difference between Jackson json and what RestEasy produces, from I think Jettison?   I also took the example from User doc section 19.6.1 JSON and JAXB collections/arrays



[{"foo":{"@test":"bill"}},{"foo":{"@test":"monica}"}}] and tried to marshal that back to object form - getting the same error.



It seems like from Jackson, I would get something like:

[{"@test":"bill"},{"@test":"monica}"}] for a List<Foo> - the difference being the {foo: } which looks like a wrapper for the object.



I changed the code to return List<Customer> instead of the Response with GenericEntity including the List<Customer> but the json looks the same.



What am I doing wrong?



Are we using the Response object incorrectly?  What's really the difference between returning List<Customer> vs Response with the List<Customer> in the generic entity?



I hope this is clear, but I can provide more details if needed.