Is it possible to check whether a page is old (in that case this page will be skipped by the test) by evaluating the If-Modified-Since HTTP header property of a page?
Is it possible to check this before the page is completely loaded, therefore saving some bandwith and time?
I am using RemoteWebDriver()
Your best bet might be to use BrowserMob Proxy, which is designed to work with Selenium and capture the HTTP traffic taking place during your test. I created BrowserMob Proxy based on the code we developed in Selenium RC (I'm the creator of that) and BrowserMob (a cloud performance testing service).
I'm not aware there's a built-in way to get the header specifically. You can instead use driver.getPageSource() and then parse the HTML with something like JSoup or Jericho.
Alternatively, cast your WebDriver object to a JavascriptExecutor and do this:
( (JavascriptExecutor) driver).executeScript("return document.lastModified;");
If-Modified-Sinceis an http request header. Do you meanLast-Modified?