java生成excel表格和pdf并实现下载弹出框

标签：style   http   java   文件   数据   os   

今天在pdf和excel中都实现了在浏览器弹出下载框

将之前在网上查找的生成excel表格代码稍微修改下：

public class CreateSimpleExcelToDisk {
 /**
  * @功能：手工构建一个简单格式的Excel
  */
 private static List<News> getNews() throws Exception
 {
  List<News> data = new ArrayList<News>();
  NewsDao dao = new NewsDao();
  ArrayList<News> list=dao.queryAll();
  SimpleDateFormat df = new SimpleDateFormat("yyyy-mm-dd");
  for(News news:list){
//	  News user1 = new News(news.getNewsId(),news.getTypeId(), news.getTitle(), news.getPublishTime(), news.getBody(),news.getTag(),news.getAuthor(),news.getClicks(),news.getImgUrl());
	  data.add(new News(news.getNewsId(),news.getTypeId(), news.getTitle(), news.getPublishTime(), news.getBody(),news.getTag(),news.getAuthor(),news.getClicks(),news.getImgUrl()));
  }
  return list;
 }
 public void ExpExcel(OutputStream out) throws Exception{

	  // 第一步，创建一个webbook，对应一个Excel文件
	  HSSFWorkbook wb = new HSSFWorkbook();
	  // 第二步，在webbook中添加一个sheet,对应Excel文件中的sheet
	  HSSFSheet sheet = wb.createSheet("Sheet1");
	  // 第三步，在sheet中添加表头第0行,注意老版本poi对Excel的行数列数有限制short
	  HSSFRow row = sheet.createRow((int) 0);
	  // 第四步，创建单元格，并设置值表头 设置表头居中
	  HSSFCellStyle style = wb.createCellStyle();
	  style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 创建一个居中格式
	  HSSFCell cell = row.createCell((short) 0);
	  // 设置编码格式
	  cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	  cell.setCellValue("newsid");
	  cell.setCellStyle(style);
	  cell = row.createCell((short) 1);
	  // 设置编码格式
	  cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	  cell.setCellValue("typeid");
	  cell.setCellStyle(style);
	  cell = row.createCell((short) 2);
	  // 设置编码格式
	  cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	  cell.setCellValue("title");
	  HSSFCellStyle style2 = wb.createCellStyle();
	  style2.setAlignment(HSSFCellStyle.ALIGN_LEFT); // 创建一个居左格式
	  cell.setCellStyle(style2);
	  cell = row.createCell((short) 3);
	  // 设置编码格式
	  cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	  cell.setCellValue("publishtime");
	  cell.setCellStyle(style);
	  cell = row.createCell((short) 4);
	  // 设置编码格式
	  cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	  cell.setCellValue("body");
	  cell.setCellStyle(style);
	  cell = row.createCell((short) 5);
	  // 设置编码格式
	  cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	  cell.setCellValue("tag");
	  cell.setCellStyle(style);
	  cell = row.createCell((short) 6);
	  // 设置编码格式
	  cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	  cell.setCellValue("author");
	  cell.setCellStyle(style);
	  cell = row.createCell((short) 7);
	  // 设置编码格式
	  cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	  cell.setCellValue("clicks");
	  cell.setCellStyle(style);
	  cell = row.createCell((short) 8);
	  // 设置编码格式主要是解决导出中文等的乱码
	  cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	  cell.setCellValue("imgUrl");
	  cell.setCellStyle(style);
	  // 第五步，写入实体数据 实际应用中这些数据从数据库得到，
	  List list = CreateSimpleExcelToDisk.getNews();
	  for (int i = 0; i < list.size(); i++)
	  {
	   row = sheet.createRow((int) i + 1);
	   News news = (News) list.get(i);
	   // 第四步，创建单元格，并设置值
	   cell = row.createCell((short) 0);
	   // 设置编码格式
	   cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	   cell.setCellValue(news.getNewsId());
	   cell.setCellStyle(style);
	   cell = row.createCell((short) 1);
	   // 设置编码格式
	   cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	   cell.setCellValue(news.getTypeId());
	   cell.setCellStyle(style);
	   cell = row.createCell((short) 2);
	   // 设置编码格式
	   cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	   cell.setCellValue(news.getTitle());
	   cell.setCellStyle(style);
	   cell = row.createCell((short) 3);
	   // 设置编码格式
	   cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	   cell.setCellValue(news.getPublishTime());
	   cell.setCellStyle(style);
	   cell = row.createCell((short) 4);
	   // 设置编码格式
	   cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	   cell.setCellValue(news.getBody());
	   cell.setCellStyle(style);
	   cell = row.createCell((short) 5);
	   // 设置编码格式
	   cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	   cell.setCellValue(news.getTag());
	   cell.setCellStyle(style);
	   cell = row.createCell((short) 6);
	   // 设置编码格式
	   cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	   cell.setCellValue(news.getAuthor());
	   cell.setCellStyle(style);
	   cell = row.createCell((short) 7);
	   // 设置编码格式
	   cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	   cell.setCellValue(news.getClicks());
	   cell.setCellStyle(style);
	   cell = row.createCell((short) 8);
	   // 设置编码格式
	   cell.setEncoding(HSSFCell.ENCODING_UTF_16);
	   cell.setCellValue(news.getImgUrl());
	   cell.setCellStyle(style);
	   /*row.createCell((short) 0).setCellValue( news.getNewsId());
	   row.createCell((short) 1).setCellValue(news.getTypeId());
	   row.createCell((short) 2).setCellValue(news.getTitle());
	//   cell = row.createCell((short) 3);
	//   cell.setCellValue(new SimpleDateFormat("yyyy-mm-dd").format(news.getPublishTime()));
	   row.createCell((short) 3).setCellValue(news.getPublishTime());
	   row.createCell((short) 4).setCellValue(news.getBody());
	   row.createCell((short) 5).setCellValue(news.getTag());
	   row.createCell((short) 6).setCellValue(news.getAuthor());
	   row.createCell((short) 7).setCellValue(news.getClicks());
	   row.createCell((short) 8).setCellValue(news.getImgUrl());*/
	  }
	  // 第六步，将文件存到指定位置
	  try
	  {
//	   String outputFile = "E:/news.xls";
//	   FileOutputStream fout = new FileOutputStream(outputFile);//"E:/news.xls"
	   System.out.println("list="+list);
	   wb.write(out);
	   out.close();
	  }
	  catch (Exception e)
	  {
	   e.printStackTrace();
	  }
 }

}

用servlet实现下载：此代码可以套用
public class ExpExcelServlet extends HttpServlet {
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		String fileName = "news.et";
		response.setContentType("octets/stream");
		response.addHeader("Content-Disposition", "attachment;filename="
				+ URLEncoder.encode(fileName, "utf-8"));
		

		try {
			NewsDao dao = new NewsDao();
			ArrayList<News> list = dao.queryAll();
			CreateSimpleExcelToDisk ce=new CreateSimpleExcelToDisk();
					OutputStream out = response.getOutputStream();
				ce.ExpExcel(out);
				out.close();
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			System.out.println("et导出成功！");
		} 

	
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doGet(request,response);
	}

}

网上的资料

可以采用：
1、RequestDispatcher的方式进行；
2、采用文件流输出的方式下载。

1、采用RequestDispatcher的方式进行
            jsp页面中添加如下代码：
           <%
      response.setContentType("application/x-download");//设置为下载application/x-download
      String filedownload = "/要下载的文件名";//即将下载的文件的相对路径
      String filedisplay = "最终要显示给用户的保存文件名";//下载文件时显示的文件保存名称
      filenamedisplay = URLEncoder.encode(filedisplay,"UTF-8");
      response.addHeader("Content-Disposition","attachment;filename=" + filedisplay);
    
      try
      {
          RequestDispatcher dis = application.getRequestDispatcher(filedownload);
          if(dis!= null)
          {
              dis.forward(request,response);
          }
          response.flushBuffer();
      }
      catch(Exception e)
      {
          e.printStackTrace();
      }
      finally
      {
    
      }
%>
2、采用文件流输出的方式下载
         <%@page language="java" contentType="application/x-msdownload"    pageEncoding="gb2312"%><%
      //关于文件下载时采用文件流输出的方式处理：
      //加上response.reset()，并且所有的％>后面不要换行，包括最后一个；
      response.reset();//可以加也可以不加
      response.setContentType("application/x-download");
      String filedownload = "想办法找到要提供下载的文件的物理路径＋文件名";
      String filedisplay = "给用户提供的下载文件名";
      filedisplay = URLEncoder.encode(filedisplay,"UTF-8");
      response.addHeader("Content-Disposition","attachment;filename=" + filedisplay);
      OutputStream outp = null;
      FileInputStream in = null;
      try
      {
          outp = response.getOutputStream();
          in = new FileInputStream(filenamedownload);
          byte[] b = new byte[1024];
          int i = 0;
          while((i = in.read(b)) > 0)
          {
              outp.write(b, 0, i);
          }
          outp.flush();
      }
      catch(Exception e)
      {
          System.out.println("Error!");
          e.printStackTrace();
      }
      finally
      {
          if(in != null)
          {
              in.close();
              in = null;
          }
          if(outp != null)
          {
              outp.close();
              outp = null;
          }
      }
%>
在wsad里面写JSP文件下载,总是出现这个异常,getOutputStream() has already been called for this response,输出流已经被调用了.
      上网查半天终于明白一点,JSP早下载文件的时候用到了OutputStream,而在Application Server在处理编译jsp时对于％>和<％之间的内容一般是原样输出，而且默认是PrintWriter.

java生成excel表格和pdf并实现下载弹出框,布布扣,bubuko.com

java生成excel表格和pdf并实现下载弹出框

标签：style   http   java   文件   数据   os   

原文地址：http://blog.csdn.net/qianquan003/article/details/37692985