Workbook workbook = new Workbook("Book1.xlsx");
SheetPrintingPreview sheetPrintingPreview = new SheetPrintingPreview(workbook.getWorksheets().get(0), new ImageOrPrintOptions());
//fastest way to get page count especailly when there are massive data in worksheet.
System.out.println(sheetPrintingPreview.getEvaluatedPageCount());