Servlet获取表单中上传文件流

private InputStream getFileInputStream(){boolean isUpload = ServletFileUpload.isMultipartContent(request);if ( isUpload ) {DiskFileItemFactory factory = new DiskFileItemFactory();ServletFileUpload upload = new ServletFileUpload(factory);try {   List<FileItem> items = upload.parseRequest(request); //解析request请求Iterator iter = items.iterator();while (iter.hasNext()) {   FileItem item = (FileItem) iter.next();   if (!item.isFormField()) {                     //如果是表单域 ，就是非文件上传元素    //String fieldName = item.getFieldName();      //文件域中name属性的值   String filePath = item.getName();            //文件的全路径，绝对路径名加文件名              //String contentType = item.getContentType(); //文件的类型   //long size = item.getSize();                  //文件的大小，以字节为单位    File saveFile = new File(filePath);      //定义一个file指向一个具体的文件   FileInputStream  in = new FileInputStream(saveFile);   return in;       }    }}catch(Exception e) {}}return null;}