 <p>You are casting the short to AppCacheStatus object below, hence the error.</p> <pre><code> AppCacheStatus status = ((ApplicationCache) (driver)).getStatus(); </code></pre> <p><a href="http://selenium.googlecode.com/svn/trunk/docs/api/java/org/openqa/selenium/html5/ApplicationCache.html#getStatus%28%29" rel="nofollow">ApplicationCache</a> is an interface so you have to write your own version of getStatus method.</p> <p>You may want to get the cache status using the JavaScriptExecutor. Hope that helps.</p> <pre><code>JavascriptExecutor jsExecutor = (JavascriptExecutor) driver; long cacheStatus = (long) jsExecutor.executeScript("return window.applicationCache.status;"); System.out.println(cacheStatus); </code></pre>