public class ExportCSV {
   /**
  * CSV文件生成方法
  * @param head
  * @param dataList
  * @param outPutPath
  * @param filename
  * @return
  */
 public static File createCSVFile(List<Object> head, List<List<Object>> dataList,
         String outPutPath, String filename) {

     File csvFile = null;
     BufferedWriter csvWtriter = null;
     try {
         csvFile = new File(outPutPath + File.separator + filename + ".csv");
         File parent = csvFile.getParentFile();
         if (parent != null && !parent.exists()) {
             parent.mkdirs();
         }
         csvFile.createNewFile();

         // GB2312使正确读取分隔符","
         csvWtriter = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
                 csvFile), "GB2312"), 1024);
         // 写入文件头部
         writeRow(head, csvWtriter);

         // 写入文件内容
         for (List<Object> row : dataList) {
             writeRow(row, csvWtriter);
         }
         csvWtriter.flush();
     } catch (Exception e) {
         e.printStackTrace();
     } finally {
         try {
             csvWtriter.close();
         } catch (IOException e) {
             e.printStackTrace();
         }
     }
     return csvFile;
 }
 /**
  * 写一行数据方法
  * @param row
  * @param csvWriter
  * @throws IOException
  */
 private static void writeRow(List<Object> row, BufferedWriter csvWriter) throws IOException {
     // 写入文件头部
     for (Object data : row) {
         StringBuffer sb = new StringBuffer();
         String rowStr = sb.append("\"").append(data).append("\",").toString();
         csvWriter.write(rowStr);
     }
     csvWriter.newLine();
 }
 public File createCSVFile(HttpServletRequest request,ResultSet rs,Object[] head,String fileNames,String outPutPath) throws Exception{

     // 设置表格头
     List<Object> headList = Arrays.asList(head);        
     // 设置数据
     List<List<Object>> dataList = new ArrayList<List<Object>>();
     List<Object> rowList = null;
   while (rs.next()) {
      rowList = new ArrayList<Object>();
      for (int i = 0; i < head.length; i++) {
           rowList.add(rs.getString(i+1));
        }
          dataList.add(rowList);
   }
     // 导出文件路径
     //String downloadFilePath = "C:" + File.separator + "系统日志" + File.separator + "download" + File.separator;
//     String downloadFilePath = "C:" + File.separator;
//     // 导出文件名称
     Date d = new Date();
     SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
     String dateNowStr = sdf.format(d);
//     String fileName = "导出操作日志数据" + dateNowStr;          
     fileNames = fileNames+dateNowStr;
     // 导出CSV文件
     File csvFile = createCSVFile(headList, dataList, outPutPath, fileNames);
//     File csvFile = createCSVFile(headList, dataList, downloadFilePath, fileNames);

     return csvFile;
 }

2.。class 调用 csv构造文件

             rs = userList(conn, sql);// 得到结果集
//          得到下载路径start
            JFileChooser jfc=new JFileChooser();
            jfc.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES );
            jfc.showDialog(new JLabel(), "选择");
            File file=jfc.getSelectedFile();
//             System.out.println("文件夹:"+file.getAbsolutePath());
            String outPutPath = file.getAbsolutePath();
//          得到下载路径end

//          这个是导出csv文件start
            Object[] head ={ "用户名", "操作时间", "操作模块", "操作内容" };// 标题 
            ExportCSV exportCsv = new ExportCSV();
//          String outPutPath="C:";
            exportCsv.createCSVFile(request, rs, head, "导出操作日志数据",outPutPath);
//          这个是导出csv文件end

            //这个是导出excel start
//          Workbook wb = new HSSFWorkbook();
//          String headers[] = { "用户名", "操作时间", "操作模块", "操作内容" };// 标题
//          fillExcelData(rs, wb, headers);
//          export(response, wb, "导出操作日志数据.xls");
            //这个是导出excel end