protected void initWorkbookAndSheet(final int startRowNumber) throws Exception {
queue = new ArrayBlockingQueue<Object>(queueCapacity == 0 ? MAX_WORKSHEET_ROWS : queueCapacity);
final POIFSFileSystem poifs = new POIFSFileSystem(inputStream);
// get the Workbook (excel part) stream in a InputStream
documentInputStream = poifs.createDocumentInputStream("Workbook");
final HSSFRequest req = new HSSFRequest();
final MissingRecordAwareHSSFListener missingRecordAwareHSSFListener = new MissingRecordAwareHSSFListener(new HSSFListenerImpl(this));
formatListener = new FormatTrackingHSSFListener(missingRecordAwareHSSFListener);
req.addListenerForAllRecords(formatListener);
final HSSFEventFactory factory = new HSSFEventFactory();
if (objectMapper == null) {
initJsonFactoryAndObjectMapper();
}