Jersey CORS working for GET but not POST

Question

My Jersey CORS request is not functioning for POST, but works for GET requests. The headers are being mapped to Jersey requests as shown in the below screenshot of a GET request to the same resource.

However, doing a POST to the below method makes me end up with XMLHttpRequest cannot load http://production.local/api/workstation. Origin http://workstation.local:81 is not allowed by Access-Control-Allow-Origin.

Here's a screenshot of network activity:

Details on failed POST request:

Here's my resource:

@Path("/workstation")
@Consumes({MediaType.APPLICATION_JSON})
@Produces({MediaType.APPLICATION_JSON})
public class WorkstationResource {

    @InjectParam
    WorkstationService workstationService;

    @POST
    public WorkstationEntity save (WorkstationEntity workstationEntity) {
        workstationService.save(workstationEntity);
        return workstationEntity;
    }

    @GET
    @Path("/getAllActive")
    public Collection<WorkflowEntity> getActive () {
        List<WorkflowEntity> workflowEntities = new ArrayList<WorkflowEntity>();
        for(Workflow workflow : Production.getWorkflowList()) {
            workflowEntities.add(workflow.getEntity());
        }
        return workflowEntities;
    }
}

My CORS filter:

public class ResponseCorsFilter implements ContainerResponseFilter {

    @Override
    public ContainerResponse filter(ContainerRequest request, ContainerResponse response) {

        Response.ResponseBuilder responseBuilder = Response.fromResponse(response.getResponse());
        responseBuilder
                .header("Access-Control-Allow-Origin", "*")
                .header("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE, HEAD");

        String reqHead = request.getHeaderValue("Access-Control-Request-Headers");

        if(null != reqHead && !reqHead.equals(null)){
            responseBuilder.header("Access-Control-Allow-Headers", reqHead);
        }

        response.setResponse(responseBuilder.build());

        return response;
    }
}

My Jersey configuration in my Main class:

//add jersey servlet support
ServletRegistration jerseyServletRegistration = ctx.addServlet("JerseyServlet", new SpringServlet());
jerseyServletRegistration.setInitParameter("com.sun.jersey.config.property.packages", "com.production.resource");
jerseyServletRegistration.setInitParameter("com.sun.jersey.spi.container.ContainerResponseFilters", "com.production.resource.ResponseCorsFilter");
jerseyServletRegistration.setInitParameter("com.sun.jersey.api.json.POJOMappingFeature", Boolean.TRUE.toString());
jerseyServletRegistration.setInitParameter("com.sun.jersey.config.feature.DisableWADL", Boolean.TRUE.toString());
jerseyServletRegistration.setLoadOnStartup(1);
jerseyServletRegistration.addMapping("/api/*");

Answer 1

While I thought this was a CORS issue, turns out it was a Jersey issue...

org.glassfish.grizzly.servlet.ServletHandler on line 256 handles an exception...

    FilterChainInvoker filterChain = getFilterChain(request);
    if (filterChain != null) {
        filterChain.invokeFilterChain(servletRequest, servletResponse);
    } else {
        servletInstance.service(servletRequest, servletResponse);
    }
} catch (Throwable ex) {
    LOGGER.log(Level.SEVERE, "service exception:", ex);
    customizeErrorPage(response, "Internal Error", 500);
}

In my log, all I see is service exception: with nothing after it. When I debug this line, I end up seeing the error javax.servlet.ServletException: org.codehaus.jackson.map.JsonMappingException: Conflicting setter definitions for property "workflowProcess": com.production.model.entity.WorkstationEntity#setWorkflowProcess(1 params) vs com.production.model.entity.WorkstationEntity#setWorkflowProcess(1 params) which gives me something I can actually work with.