code: @Path(JaxRxConstants.JAXRXPATH)
      @POST
      @Consumes(APPLICATION_QUERY_XML)
      public Response postQuery(@PathParam(JaxRxConstants.SYSTEM) final String system, final InputStream input,
          @Context final HttpHeaders headers) {
          return postQuery(system, input, "", headers);
      }
docs: This method will be called when a HTTP client sends a POST request to an
  existing resource with 'application/query+xml' as Content-Type.
  
  @param system
  The implementation system.
  @param input
  The input stream.
  @param headers
  HTTP header attributes.
  @return The {@link Response} which can be empty when no response is
  expected. Otherwise it holds the response XML file.