FileInputStream inputStream = new FileInputStream(new File(templateFile));
Workbook workbook = new HSSFWorkbook(inputStream);

POIFSFileSystem fs = new POIFSFileSystem(
    	        new FileInputStream("template.xls"));
HSSFWorkbook wb = new  HSSFWorkbook(fs, true);

FileOutputStream fileOut = new FileOutputStream("new.xls");
wb.write(fileOut);
fileOut.close();