由javamail API保存的Excel文件对apache poi API不可读

我收到一个电子邮件中的文件，我使用javamail API读取并将其保存到磁盘目录中

MailExtractor.java

Multipart multiPart = (Multipart) message.getContent(); int numberOfParts = multiPart.getCount(); for (int partCount = 0; partCount < numberOfParts; partCount++) { MimeBodyPart part = (MimeBodyPart) multiPart.getBodyPart(partCount); if (Part.ATTACHMENT.equalsIgnoreCase(part.getDisposition())) { // this part is attachment String fileName = part.getFileName(); attachFiles += fileName + ", "; part.saveFile(saveDir + File.separator + fileName); } else { // this part may be the message content messageContent = part.getContent().toString(); } } 

现在另一个程序轮询该磁盘目录并读取所有传入的文件。 我只关心文件扩展名 – xls / xlsx，所以我使用apache poi来读取文件：

 /AvailabilityDirectoryPoller.java FileInputStream fs = new FileInputStream(file); Workbook wb = null; Sheet sheet = null; if(FilenameUtils.getExtension(file.getName()).equalsIgnoreCase("xls")){ wb = new HSSFWorkbook(fs); //line no 178 sheet = (HSSFSheet)wb.getSheetAt(0); } else{ wb = new XSSFWorkbook(fs); sheet = (XSSFSheet)wb.getSheetAt(0); } 

有时（随机读取）会导致错误，如下所示

 [2013-07-18 23:38:32,409] ERROR [AvailabilityDirectoryPoller]: Exception in I/O Reading file java.io.IOException: Your file contains 79 sectors, but the initial DIFAT array at index 1 referenced block # 98. This isn't allowed and your file is corrupt at org.apache.poi.poifs.storage.BlockAllocationTableReader.<init>(BlockAllocationTableReader.java:103) at org.apache.poi.poifs.filesystem.POIFSFileSystem.<init>(POIFSFileSystem.java:151) at org.apache.poi.hssf.usermodel.HSSFWorkbook.<init>(HSSFWorkbook.java:322) at org.apache.poi.hssf.usermodel.HSSFWorkbook.<init>(HSSFWorkbook.java:303) at com.db.mmrepo.app.avl.bespoke.AvailabilityDirectoryPoller.process(AvailabilityDirectoryPoller.java:178) at com.db.mmrepo.app.avl.bespoke.AvailabilityDirectoryPoller.fileFound(AvailabilityDirectoryPoller.java:73) at org.sadun.util.polling.DefaultListener.receive(DefaultListener.java:43) at com.deltax.util.listener.SignalQueue.run(Unknown Source) 

如果我打开MS Excel中保存的文件，它打开woth没有警告/错误。