Spring 如何导出当前页面的表格为Excel

现在页面上有一个按钮，写着导出，可以导出当前页面的数据为Excel,导出按钮在jsp里写着，请问，js和后台controller该怎么写？

1.前台页面
poi.jar  gson2.2.2.jar
< a href ="hello/download.htm">下载导入模板 </a>

2.后台操作

@RequestMapping("download.htm" )
       public void download(HttpServletResponse response){
           String methodName = "dowloadCmmRange";
              LOGGER.info("download_start" , methodName);
              response.setContentType( "application/vnd.ms-excel");
              String fileName = "";

              try {
                  fileName = new String("商品范围导入.csv" .getBytes("GBK"), "iso8859-1");
              } catch (UnsupportedEncodingException e) {
                  throw new BaseException("SP-CTR-CouponRuleCommonController.dowloadCmmRange" , e);
              }

              response.setHeader( "Content-Disposition", "attachment;filename=" + fileName);

              BufferedWriter bw = null;
              OutputStream outputStream = null;

              try {
                  outputStream = response.getOutputStream();
                  bw = new BufferedWriter(new OutputStreamWriter(outputStream, "GBK" ));
                  bw.append( "商品编码" ).append(",").append( "品牌编码" ).append(",")
                          .append( "品类编码" ).append(",").append( "事业部编码" )
                          .append( ",").append("供应商编码" ).append(",")
                          .append( "操作(包含I/排除E)" );
                  bw.flush();
              } catch (IOException e) {
                  throw new BaseException("SP-CTR-CouponRuleCommonController.dowloadCmmRange" , e);
              } finally {
                  if (null != outputStream) {
                      try {
                          outputStream.close();
                      } catch (IOException e) {
                          throw new BaseException("SP-CTR-CouponRuleCommonController.dowloadCmmRange" , e);
                      }
                  }
                  if (null != bw) {
                      try {
                          bw.close();
                      } catch (IOException e) {
                          throw new BaseException("SP-CTR-CouponRuleCommonController.dowloadCmmRange" , e);
                      }
                  }
              }
              LOGGER.info("download_end" , methodName);
          }

后台把数据再查出来一遍，然后调用poi，或jxl生成excel，返回给页面就行了。