用Excel导出数据（一）

按要求从表中找出数据，再以Excel形式下载，操作步骤如下：
Action类

public ActionForward doBillPackDown(BActionContext context)
			throws Exception {
		try{
			HttpServletResponse response = context.getResponse();
			response.setContentType("application/multipart");
			SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
			String TodayDate = sdf.format(new Date());
			String fileName = "Download_BillPack_" + TodayDate + ".xls";
			response.setHeader("Content-Disposition", "filename=" + fileName);
			EPickService service = (EPickService) context.findService("epickService", EPickService.class);
			String[] ids= (String[]) context.getRequest().getParameterValues("ids");
			logger.info("======电子提单明细下载开始=======");
			EPickSearchModel mdl = new EPickSearchModel();
			mdl.setIds(ids);
			HSSFWorkbook workbook = service.downBillPackDetail(mdl);
			workbook.write(response.getOutputStream());
			response.getOutputStream().flush();
			response.getOutputStream().close();
			return null;
        }catch (Exception e) {
			e.printStackTrace();
			logger.error(e);
			if (e.getMessage()!=null && e.getMessage().startsWith("msg:")) {
				context.getRequest().setAttribute("msg",
						e.getMessage().substring(4));
			} else {
				context.getRequest().setAttribute("error", e);
			}
			return context.findForward("fail");
		}
	}

ServiceImpl类：

public HSSFWorkbook downBillPackDetail(EPickSearchModel mdl)
			throws Exception {
		return epickDao.downBillPackDetail(mdl);
	}

DaoImpl类：

public HSSFWorkbook downBillPackDetail(EPickSearchModel mdl)
			throws Exception {
		String[] billIds = mdl.getIds();
		StringBuffer hql = new StringBuffer();
		hql.append("select t.billId,t.orderNum,t.shopsign,t.specDesc,t.packId,t.netWeight,t.grossWeight" +
				" from TplBillPack t where t.billNum in (");
		int idSize = billIds.length;
		for (int i=0; i<idSize-1;i++ ){
			hql.append(""+new String(billIds[i]) + ",");
		}
		hql.append(""+new String(billIds[idSize-1]) + ")");
		hql.append(" order by t.billId, t.orderNum");
		List billPackList = this.queryByHql(hql.toString());
		//实例化一个hssfworkbook对象
		HSSFWorkbook wb = new HSSFWorkbook();
		downBillPackDetailHelp(wb,billPackList);
		return wb;
	}

public void downBillPackDetailHelp(HSSFWorkbook wb, List billPackList)throws Exception{
		try{
			Object [] objHead=getHeadFromBillPack();
			LinkedList headList=(LinkedList)objHead[0];
			
			//创建一个sheet
			HSSFSheet sheet = wb.createSheet("contract_list");
			
			//设置单元格的样式
			HSSFCellStyle cellStyle0 = wb.createCellStyle();
	        cellStyle0.setAlignment(HSSFCellStyle.ALIGN_CENTER);
	        cellStyle0.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
	        
			short rownum = 0; 
			//创建第一行
			HSSFRow srow = sheet.createRow(rownum);		     
//			HSSFCell cellHead = null;
//			srow = sheet.createRow( (short) rownum);
//			
//	        srow.setHeightInPoints(30);//设置高度  
//	        cellHead = srow.createCell((short) 0);
//	        cellHead.setEncoding(HSSFCell.ENCODING_UTF_16);//设置编码
//	        cellHead.setCellValue("电子提单明细"); //单元格内容
//			cellHead.setCellStyle(cellStyle0);  //单元格样式
//			
//			srow = sheet.createRow( (short) 1);
//			//srow.setHeight( (short) 300); 
//			rownum++;
//			srow = sheet.createRow(rownum);
			
			for (int i = 0; i < headList.size(); i++){
				HSSFCell cell = srow.createCell((short) (i));      
				cell.setEncoding(HSSFCell.ENCODING_UTF_16);
				cell.setCellValue(headList.get(i).toString());
			}

			for(Iterator it = billPackList.iterator();it.hasNext();) {
				Object[] obj = (Object[])it.next();
				rownum++;
				srow = sheet.createRow(rownum);
				for (int j = 0; j < headList.size(); j++) {
					HSSFCell cell=srow.createCell((short)j);
					if(obj[j]==null)
						cell.setCellValue("");
					else
						cell.setCellValue(obj[j].toString());
				}
			}
		}catch(Exception e){
			e.printStackTrace();
		}
	}
	
	/**
	 * 获取Excel第一行标题
	 * @return
	 */
	private Object []getHeadFromBillPack(){
		List head =new LinkedList();
		head.add("提单号");
		head.add("合同号");
		head.add("牌号");
		head.add("规格");
		head.add("捆包号");
		head.add("净重");
		head.add("毛重");
		
		Object [] obj=new Object[1];
		obj[0]=head;
		return obj;
	}

jsp页面中的js代码：

function billPackDown(){
		var ids = document.getElementsByName('checkbox');
		var ids_java = new Array();
		var count = 0;
		var msg = "";
					
		if(ids.length == 0)
		{
			alert("现在没有记录信息，不能下载!");
			return;
		}
					
		for(i=0; i < ids.length; i++)
		{
			if(ids[i].checked)
			{
				count ++;
				ids_java.push(ids[i].value);
			}
		}
		
		if(count < 1 || count > 5)
		{
			alert("电子提单明细下载需至少选择1条且不多于5条的提单记录!");
			return;
		}
		
		if (msg != ""){
		    msg += "请用户重新选择！";
		    alert(msg);
		    return;
		} 
		
		window.open('../ePick/ePickPrintManage.do?method=billPackDown&ids='+ids_java,'','width=800,height=500,top=100,left=150,scrollbars=yes,resizable=yes');
	}