0
点赞
收藏
分享

微信扫一扫

web中使用POI的例子


web中使用POI的例子

struts1.x的例子,struts2.x可以参考自己修改



1.action的写法


 



import
   java.io.
  *
  ;
  import
   java.sql.
  *
  ;
  import
   java.util.ArrayList;

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

  import
   org.apache.poi.hssf.usermodel.
  *
  ;
  import
   org.apache.struts.action.
  *
  ;
  import
   org.apache.struts.upload.FormFile;
  import
   org.apache.commons.beanutils.BeanUtils;

  public
   
  class
   Action 
  
  {
 /**//*
  * 把数据库中的字段导入到Excel ,并生成Excel文档
  **/
 public ActionForward getDownload(ActionMapping actionMapping,
   ActionForm actionForm, HttpServletRequest request,
   HttpServletResponse response) throws Exception 
{
  Form fm = (Form) actionForm;
  // Excel 文件存放在服务器的相对路径下
  String outputFile = request.getRealPath("/tmp/Excel.xls");
  
  try 
{
   // 创建新的Excel 工作簿
   HSSFWorkbook workbook = new HSSFWorkbook();
   // 在Excel 工作簿中建一工作表
   HSSFSheet sheet = workbook.createSheet("Sheet1");
   // 设置单元格格式(文本)
   HSSFCellStyle cellStyle = workbook.createCellStyle();
   cellStyle.setDataFormat(HSSFDataFormat.getBuiltinFormat("@"));
   
   // 在索引0的位置创建行(第一行)
   HSSFRow row = sheet.createRow((short) 0);
   
   HSSFCell cell1 = row.createCell((short) 0);// 第一列
   HSSFCell cell2 = row.createCell((short) 1);
   HSSFCell cell3 = row.createCell((short) 2);
   // 定义单元格为字符串类型
   cell1.setCellType(HSSFCell.CELL_TYPE_STRING);
   cell2.setCellType(HSSFCell.CELL_TYPE_STRING);
   cell3.setCellType(HSSFCell.CELL_TYPE_STRING);
   
   cell1.setEncoding(HSSFCell.ENCODING_UTF_16);
   cell2.setEncoding(HSSFCell.ENCODING_UTF_16);
   cell3.setEncoding(HSSFCell.ENCODING_UTF_16);
   // 在单元格中输入数据
   cell1.setCellValue("姓名");
   cell2.setCellValue("性别");
   cell3.setCellValue("年龄");
   
   Connection connection = session.connection();
   
   String sql = "Select t.name, t.sex, t.age from table t where t.sex = ?";
   
   try 
{
    PreparedStatement ps = connection.prepareStatement(sql);
    ps.setString(1, fm.getSex());// 传入查询条件
    ResultSet rs = ps.executeQuery();// 查询结果存入rs
    connection.commit();// 执行SQL
    
    while (rs.next()) 
{
    //设置j行从第二行开始
     int j = 1;
     row = sheet.createRow((short) j);
     //设置i列从第二列开始
     for (int i = 1; i <= 3; i++) 
{
      HSSFCell cell = row.createCell((short) (i-1));
      // 设置单元格格式
      cell.setCellStyle(cellStyle);
      cell.setCellType(HSSFCell.CELL_TYPE_STRING);
      cell.setEncoding(HSSFCell.ENCODING_UTF_16);
      cell.setCellValue(rs.getString(i));
     }
     
     j++;
    }
    
    request.setAttribute("message", "文件生成成功!");
   } catch (SQLException e) 
{
    request.setAttribute("message", "创建文件失败!");
    e.printStackTrace();
   }
   // 删除路径下同名的Excel 文件
   File path = new File(outputFile);
   path.delete();
   
   // 新建一输出文件流
   FileOutputStream fOut = new FileOutputStream(outputFile);
   // 把相应的Excel 工作簿存盘
   workbook.write(fOut);
   // 操作结束,关闭文件
   fOut.flush();
   fOut.close();
    //该处如果Excel过大会影响效率,谁有好的想法可以提出来参考(不过从页面下载完后就会清空)
   request.getSession().setAttribute("Download", outputFile);
   
  } catch (Exception ioexception) 
{
   request.setAttribute("message", "创建文件失败!");
   return actionMapping.findForward("outJSP");
  }
  
  return actionMapping.findForward("outJSP");
 }
 
 /**//*
  * 从Excel文件中读取数据,并导入到数据库中
  **/
  public ActionForward getUpload(ActionMapping actionMapping,
   ActionForm actionForm, HttpServletRequest request,
   HttpServletResponse response) throws Exception 
{
  // 获取excel 文件
  Form fm = (Form) actionForm;
  FormFile formfile = fm.getUploadfile();
  InputStream inputstream = formfile.getInputStream();
  fm.clear();// 清空
  Session session = HibernateSession.currentSession();
  ArrayList list = new ArrayList();
  int input = 0; //导入记数
  String name = null;
  String sex = null;
  String age = null;
  
  try 
{
   //通过得到的文件输入流inputstream创建一个HSSFWordbook对象
         HSSFWorkbook hssfworkbook = new HSSFWorkbook(inputstream);
         HSSFSheet hssfsheet = hssfworkbook.getSheetAt(0);//第一个工作表
   HSSFRow hssfrow = hssfsheet.getRow(0);//第一行
   
   //遍历该表格中所有的工作表,i表示工作表的数量 getNumberOfSheets表示工作表的总数
            for (int i = 0; i < hssfworkbook.getNumberOfSheets(); i++) 
{
             hssfsheet = hssfworkbook.getSheetAt(i);
             
             //遍历该行所有的行,j表示行数 getPhysicalNumberOfRows行的总数
                for (int j = 1; j < hssfsheet.getPhysicalNumberOfRows(); j++) 
{
                 hssfrow = hssfsheet.getRow(j);
                 //判断是否还存在需要导入的数据
                    if (hssfrow == null) 
{
                     System.out.println("这里已没有数据,在第"+i+"列,第"+j+"行");
                     break;
                    }
                    /** *//**将EXCEL中的第 j 行,第一列的值插入到实例中*/
                    if (hssfrow.getCell((short) 0) == null) 
{
                     name = "";
                    } else if (hssfrow.getCell((short) 0).getCellType() == 0) 
{
                     name = new Double(hssfrow.getCell((short) 0).getNumericCellValue()).toString();
                    }
                    //如果EXCEL表格中的数据类型为字符串型
                    else 
{
                     name = hssfrow.getCell((short) 0).getStringCellValue().trim();
                    }
                    /** *//**将EXCEL中的第 j 行,第二列的值插入到实例中*/
                    //姓名
                    if(hssfrow.getCell((short) 1) == null)
{
                     sex = "";
                    } else if(hssfrow.getCell((short) 1).getCellType() == 0) 
{
                        sex = new Double(hssfrow.getCell((short) 1).getNumericCellValue()).toString();
                    }
                    //如果EXCEL表格中的数据类型为字符串型
                    else 
{
                        sex = hssfrow.getCell((short) 1).getStringCellValue().trim();
                    }
                    /** *//**将EXCEL中的第 j 行,第三列的值插入到实例中*/
                    //姓名
                    if(hssfrow.getCell((short) 1) == null)
{
                     age = "";
                    } else if(hssfrow.getCell((short) 1).getCellType() == 0) 
{
                        age = new Double(hssfrow.getCell((short) 1).getNumericCellValue()).toString();
                    }
                    //如果EXCEL表格中的数据类型为字符串型
                    else 
{
                        age = hssfrow.getCell((short) 1).getStringCellValue().trim();
                    }
                    
                    name = name.trim();
                    sex = sex.toUpperCase();
                    
                    if (name.equals("")) 
{
                     error.setName(name);
                     error.setMessage("姓名不能为空");
                     
                     list.add(error);
                     continue;
                    } else 
{
                     fm.setName(name);
                     fm.setSex(sex);
                     fm.setAge(age);
                     
                     session.save(fm);
                    }
                    //导入成功加1
                    input++;
                }
            }
            
            session.saveObjs(list.toArray());
        } catch () 
{
         
        }
 }
}



2.Form的写法



import   org.apache.struts.action.ActionForm;
  import
   org.apache.struts.upload.FormFile;

  public
   
  class
   Form 
  extends
   ActionForm 
  
  {
 // 上传的文件
 private FormFile _flddo;
 
 public void setUploadfile(FormFile formfile) 
{
  _flddo = formfile;
 }
 
 public FormFile getUploadfile() 
{
  return _flddo;
 }
 
 public void clear() 
{
  _flddo = null;
 }
}





3.上传页面Upload.jsp





<%
  
  @ page contentType="text/html; charset=GBK" language="java"
  %>
  
  <%
  
  @ taglib uri="http://jakarta.apache.org/struts/tags-html" prefix="html"
  %>
  

  <
  html
  >
  
   <  html:form 
  action
  ="/Action.do?method=getUpload"
   method
  ="POST"
   enctype
  ="multipart/form-data"
  >
  
    <  html:file 
  property
  ="uploadfile"
   size
  ="80%"
   
  />
  
    <  input 
  type
  ="button"
   value
  ="导 入"
   onclick
  ="upload(this.form)"
   class
  ="buttonGray"
  >
  
   </  html:form
  >
  
  </
  html
  >
  

  <
  script 
  language
  ="javascript"
  >
  
  
function upload(obj)
{
 if(confirm("您现在选择的是XXX,您确定要导入吗?"))
 
{
  var uploadfile = document.all.uploadfile.value;
  if((null == uploadfile) ||( "" == uploadfile))
  
{
   alert("上传文件没有指定!");
   return false;
  }
     obj.action = '<html:rewrite page="/Action.do?method=getUpload"/>';
     obj.submit();
 }
}
  </
  script
  >



4.下载页面Download.jsp




<%
 
 @ page contentType="text/html; charset=GBK"
 %>
 
 <%
 
 @ taglib uri="http://jakarta.apache.org/struts/tags-html" prefix="html" 
 %>
 
 <%
 
 @ taglib uri="http://jakarta.apache.org/struts/tags-bean" prefix="bean" 
 %>
 

 <%
 
 
//获取下载文件
 String download = (String) request.getSession().getAttribute("Download");
//清空文件
 request.getSession().removeAttribute("Download");
 %>
 

 <
 html
 >
 
 下传文件  < a  href
 ="<%=download %>"
  name
 ="下载"
 >
 下载
 </
 a
 >
 
 </
 html
 >

举报

相关推荐

0 条评论