code: /** 
   * Verify setting number header
   * @throws Exception
   */
  @Test public void numberHeader() throws Exception {
    final AtomicReference<String> h1=new AtomicReference<String>();
    final AtomicReference<String> h2=new AtomicReference<String>();
    handler=new RequestHandler(){
      @Override public void handle(    Request request,    HttpServletResponse response){
        response.setStatus(HTTP_OK);
        h1.set(request.getHeader("h1"));
        h2.set(request.getHeader("h2"));
      }
    }
  ;
    assertTrue(get(url).header("h1",5).header("h2",(Number)null).ok());
    assertEquals("5",h1.get());
    assertEquals("",h2.get());
  }
  