public XlsDataSet(InputStream in) throws IOException, DataSetException
public XlsDataSet(File file) throws IOException, DataSetException
    public XlsDataSet(InputStream in) throws IOException, DataSetException    {        HSSFWorkbook workbook = new HSSFWorkbook(in);        _tables = new ITable[workbook.getNumberOfSheets()];        for (int i = 0; i < _tables.length; i++)        {            _tables[i] = new XlsTable(workbook.getSheetName(i),                    workbook.getSheetAt(i));        }    }