excel导出 jxl.jar包

导入jxl.jar包， 代码如下：

package com.gree;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.sql.PreparedStatement;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletRequest;

import jxl.Workbook;
import jxl.format.Colour;
import jxl.format.UnderlineStyle;
import jxl.write.Label;
import jxl.write.WritableCellFormat;
import jxl.write.WritableFont;
import jxl.write.WritableSheet;
import jxl.write.WritableWorkbook;
import jxl.write.WriteException;
import jxl.write.biff.RowsExceededException;
public class CreateExcel {

    public void createxcel(HttpServletResponse res,HttpServletRequest req) throws Exception{

        OutputStream os=null;
        WritableWorkbook wwb=null;

        ConnDB db=new ConnDB();
        String str="select * from user";
        ArrayList<Student> list=db.getList(str);
        try {
            java.text.SimpleDateFormat df = new java.text.SimpleDateFormat("yyyy-MM-dd");
            String today = df.format(new java.util.Date());
     String fileName="改模时间报表-"+today;
            //System.out.println(fileName);
            fileName=new String(fileName.getBytes("gb2312"), "ISO8859_1");
            //System.out.println(fileName);
            HttpServletResponse response=res;
            HttpServletRequest request=req;

            response.reset();
            response.setContentType("APPLICATION/OCTET-STREAM");
            if (request.getHeader("User-Agent").indexOf("MSIE 5.5") != -1) { // MS
                response.setHeader("Content-Disposition", "filename="+fileName+".xls");
            } else {
                response.addHeader("Content-Disposition","attachment;filename="+fileName+".xls");
            }

            /**/
            os = response.getOutputStream();
            wwb = Workbook.createWorkbook(os);
            WritableSheet sheet = wwb.createSheet("sheet1", 0);
            jxl.write.WritableCell cell = null;

            WritableFont wf = new WritableFont(WritableFont.ARIAL,12,WritableFont.NO_BOLD,false,
            UnderlineStyle.NO_UNDERLINE,Colour.BLUE);
            WritableCellFormat formatH =  new WritableCellFormat(wf);
            formatH.setAlignment(jxl.format.Alignment.CENTRE);

            cell = new Label(0, 0,"用户表", formatH);
            sheet.addCell(cell);
            sheet.mergeCells(0,0,14,0);

            formatH = getFormat("BOLD", 9, Colour.BLACK);
            formatH.setAlignment(jxl.format.Alignment.CENTRE);
            formatH.setBorder(jxl.format.Border.ALL,jxl.format.BorderLineStyle.THIN);

            WritableCellFormat format = getFormat("NOBOLD", 9, Colour.BLACK);
            //format.setAlignment(jxl.format.Alignment.LEFT);
            format.setBorder(jxl.format.Border.ALL,jxl.format.BorderLineStyle.THIN);
            //
            cell = new Label(0, 1,"名字", formatH);
            sheet.addCell(cell);
            cell = new Label(1, 1,"密码", formatH);
            sheet.addCell(cell);
            cell = new Label(2, 1,"最后登录时间", formatH);
            sheet.addCell(cell);

            /**/

    for(int i=0;i<list.size();i++){

                cell = new Label(0, i+2, list.get(i).getName(), format);
                sheet.addCell(cell);
                cell = new Label(1, i+2, list.get(i).getPassword(), format);
                sheet.addCell(cell);
                cell = new Label(2, i+2, list.get(i).getLastlogintime(), format);
                sheet.addCell(cell);

sheet.setColumnView(0,10);
sheet.setColumnView(1,20);
sheet.setColumnView(2,20);

    }

wwb.write();

            wwb.close();
            os.close();
            response.setStatus(response.SC_OK);
            response.flushBuffer();
        } catch (RowsExceededException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (WriteException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

 WritableCellFormat getFormat(String style, int size, Colour color)
    {
    WritableFont wfc = null;
    if("BOLD".equals(style))
        wfc = new WritableFont(WritableFont.ARIAL, size, WritableFont.BOLD, false, UnderlineStyle.NO_UNDERLINE, color);
    else
    if("NOBOLD".equals(style))
        wfc = new WritableFont(WritableFont.ARIAL, size, WritableFont.NO_BOLD, false, UnderlineStyle.NO_UNDERLINE, color);
    return new WritableCellFormat(wfc);
}

}

index.jsp中代码如下，创建该对象并 调用createxcel方法导出excel表格 　　

<%
  int opt;

  if(request.getParameter("opt")==null) opt=0;

  else opt=Integer.parseInt(request.getParameter("opt"));
  if(opt==1){

   CreateExcel excel=new CreateExcel();
   excel.createxcel(response, request);

   }
   else{

    %>

   <a href="index.jsp?opt=1">导出excel表格</a> &nbsp;
   <a href="importexcel.jsp">导入excel表格</a>&nbsp;
   <%}

   }

    %>