code: /** 
   * Verify 'Accept' request header when calling {@link HttpRequest#acceptJson()}
   * @throws Exception
   */
  @Test public void acceptJson() throws Exception {
    final AtomicReference<String> header=new AtomicReference<String>();
    handler=new RequestHandler(){
      @Override public void handle(    Request request,    HttpServletResponse response){
        response.setStatus(HTTP_OK);
        header.set(request.getHeader("Accept"));
      }
    }
  ;
    assertTrue(get(url).acceptJson().ok());
    assertEquals("application/json",header.get());
  }
  