POI or Jexcel API的问题，想作导入导出excel数据的东西

Question

try {
        InputStream is = new FileInputStream("d:\\xx.xls");
        Workbook wb = Workbook.getWorkbook(is);
        jxl.write.WritableWorkbook wwb=Workbook.createWorkbook(new java.io.File("d:\\newExcel.xls"));        is.close();
        Sheet sheet = wb.getSheet(1);        WritableSheet ws = wwb.createSheet("Sheet111", 0);        //1.添加Label对象
        jxl.write.Label labelC = new jxl.write.Label(0, 0, "This is a Label cell");
        ws.addCell(labelC);        //添加带有字型Formatting的对象
        jxl.write.WritableFont wf = new jxl.write.WritableFont(WritableFont.TIMES,
            18, WritableFont.BOLD, true);
        jxl.write.WritableCellFormat wcfF = new jxl.write.WritableCellFormat(wf);
        jxl.write.Label labelCF = new jxl.write.Label(1, 0,
            "This is a Label Cell", wcfF);
        ws.addCell(labelCF);        //添加带有字体颜色Formatting的对象
        jxl.write.WritableFont wfc = new jxl.write.WritableFont(WritableFont.
            ARIAL, 10, WritableFont.NO_BOLD, false, UnderlineStyle.NO_UNDERLINE,
            jxl.format.Colour.RED);
        jxl.write.WritableCellFormat wcfFC = new jxl.write.WritableCellFormat(wfc);
        jxl.write.Label labelCFC = new jxl.write.Label(1, 0,
            "This is a Label Cell", wcfFC);
        ws.addCell(labelCFC);        //2.添加Number对象
        jxl.write.Number labelN = new jxl.write.Number(0, 1, 3.1415926);
        ws.addCell(labelN);        //添加带有formatting的Number对象
        jxl.write.NumberFormat nf = new jxl.write.NumberFormat("#.##");
        jxl.write.WritableCellFormat wcfN = new jxl.write.WritableCellFormat(nf);
        jxl.write.Number labelNF = new jxl.write.Number(1, 1, 3.1415926, wcfN);
        ws.addCell(labelNF);        //3.添加Boolean对象
        jxl.write.Boolean labelB = new jxl.write.Boolean(0, 2, false);
        ws.addCell(labelB);        ws.addRowPageBreak(1);
        //4.添加DateTime对象
        jxl.write.DateTime labelDT = new jxl.write.DateTime(0, 3,
            new java.util.Date());
        WritableCellFeatures cfDate=new WritableCellFeatures();
        cfDate.setComment("今天的日期");
        labelDT.setCellFeatures(cfDate);
        ws.addCell(labelDT);
        ws.addRowPageBreak(0);        //5.图像
        WritableImage img=new WritableImage(5,6,5,15,new java.io.File("d:\\test.png"));
        ws.addImage(img);
        //6.超级链接
        WritableHyperlink link=new WritableHyperlink(0,10,new java.net.URL("http://www.google.com"));
        link.setDescription("搜索引擎");
        ws.addHyperlink(link);        wwb.write();
        wwb.close();      }
      catch (Exception ex) {
        ex.printStackTrace();
      }