public void onUrlUpdate(Source cv, String oldUrl) { if (oldUrl == null){ sourceChangeLogger.log(Level.INFO, "The URL " + cv.getUrl() + " has been added to the source " + cv.toString()); } else if (cv.getUrl() == null){ sourceChangeLogger.log(Level.INFO, "The URL " + oldUrl + " has been removed from the source " + cv.toString()); } else { sourceChangeLogger.log(Level.INFO, "The URL " + oldUrl + " has been updated with " + cv.getUrl() + " in the source " + cv.toString()); } }