void badRequest(String s) {
    setStatus(HttpServletResponse.SC_BAD_REQUEST);
    String title = "Bad request: ";
    setTitle((s != null) ? join(title, s) : title);
  }
@Test
  public void testBadRequest() {
    String message = "test string";
    appController.badRequest(message);
    verifyExpectations(message);
  }