code: @Test public void clientSuppliedConditionWithoutCachedResult() throws Exception {
    server.enqueue(new MockResponse().setResponseCode(HttpURLConnection.HTTP_NOT_MODIFIED));
    server.play();
    HttpURLConnection connection=openConnection(server.getUrl("/"));
    String clientIfModifiedSince=formatDate(-24,TimeUnit.HOURS);
    connection.addRequestProperty("If-Modified-Since",clientIfModifiedSince);
    assertEquals(HttpURLConnection.HTTP_NOT_MODIFIED,connection.getResponseCode());
    assertEquals("",readAscii(connection));
  }
  