Weird Behavior When Dealing With POST Request Parameters

Question

I'm working on a RESTful API, using Apache CXF as my JAX-RS implementation. I have a POST endpoint that's supposed to receive a request with three parameters. Here's a snippet of my code (modified and shortened):

@Path("endpoint_path")
public class MyResource {
    @Context
    private HttpServletRequest request;

    @POST
    @Produces(MediaType.TEXT_HTML)
    @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
    public Response postEndpoint(@QueryParam("param1") String param1,
                                 @FormParam("param2") String param2,
                                 @FormParam("param3") String param3) {
        (use request as input for some library)
    }
}

Inside that method, param2 and param3 both have the expected values, but if I check the request object's parameters (by using request.getParameterNames()), I only get one parameter -param1- instead of all three. I know for sure that I'm receiving all 3 parameters, param1 as a query parameter, and param2 and param3 as form parameters, because as I just said, I get their values passed as method parameters. They just don't seem to exists inside the request object.

This puzzled me so much, that I created a Filter that only does one thing, it peeks inside the request for the parameter names and does nothing else:

public class TestCXFPostParamsFilter implements Filter {

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse,
            FilterChain filterChain) throws IOException, ServletException {

        servletRequest.getParameterNames();

        filterChain.doFilter(servletRequest, servletResponse);
    }

    (init() and destroy() empty methods)

}

and in my web.xml file, I set the filter to apply to every request to my endpoint. Now here's where things get weird - for some reason, that makes everything work, by which I mean, if I check the request object back in the endpoint method, it'll contain all three expected parameters. What sorcery is this?

As a side note, some of you may be wondering why would I bother to check the request object, when I just said I have access to the parameter values that are passed to the method by CXF's servlet? The answer is that I'm using a library that expects you to pass the request object to it, instead of just the necessary values. So I really need the request to keep its parameters inside (like I always assumed it would).

Finally, I'm using Java 6, and CXF 2.7.10 (which comes with Apache Camel CXF 2.13.0). And yes, those are more or less set in stone for all intents and purposes, so if the reason all of this is happening is because of a bug in one of these pieces, I'm stuck with an useless filter as a "solution".

Weird Behavior When Dealing With POST Request Parameters

0 Answers0