使用poi异常：Package should contain a content type part [M1.13]

public static Workbook create(InputStream in) throws

IOException,InvalidFormatException {

if (!in.markSupported()) {

in = new PushbackInputStream(in, 8);

}

if (POIFSFileSystem.hasPOIFSHeader(in)) {

return new HSSFWorkbook(in);

}

if (POIXMLDocument.hasOOXMLHeader(in)) {

return new XSSFWorkbook(OPCPackage.open(in));

}

throw new IllegalArgumentException("你的excel版本目前poi解析不了");

}

读写xls和xlsx格式时，HSSFWorkbook针对xls，XSSFWorkbook针对xlsx

参考文章：http://blog.csdn.net/llwan/article/details/8890190