@Test
  public void ifModifiedSinceHeader() throws Exception {
    final AtomicLong header = new AtomicLong();
    handler = new RequestHandler() {

      @Override
      public void handle(Request request, HttpServletResponse response) {
        response.setStatus(HTTP_OK);
        header.set(request.getDateHeader("If-Modified-Since"));
      }
    };
    assertTrue(get(url).ifModifiedSince(5000).ok());
    assertEquals(5000, header.get());
  }
Verify 'If-Modified-Since' request header

@throws Exception
lib/src/test/java/com/github/kevinsawicki/http/HttpRequestTest.java