private void readUrlFile() throws IOException {
        try (BufferedReader fileUrlReader = new BufferedReader(new FileReader(getFileName(fileUrlAllName)))) {
            String line;
            int lineReaded = 0;
            while ((line = fileUrlReader.readLine()) != null) {
                Request request = deserializeRequest(line);
                this.getDuplicateRemover().isDuplicate(request, null);
                lineReaded++;
                if (lineReaded > cursor.get()) {
                    queue.add(request);
                }
            }
        }
    }
Store urls and cursor in files so that a Spider can resume the status when shutdown.<br>

@author code4crafter@gmail.com <br>
@since 0.2.0
webmagic-extension/src/main/java/us/codecraft/webmagic/scheduler/FileCacheQueueScheduler.java