Question

这是我的view.jsp ..

代码

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@page import="java.io.File,java.util.*,java.sql.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
<html><body>
<h1> List of All Files to download </h1>
<%
Class.forName("com.mysql.jdbc.Driver");
Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql", "root", "admin");
PreparedStatement ps = conn.prepareStatement("select * from employeereg1");
ResultSet rs=ps.executeQuery();
%>
<table border=1>
<tr><td>Employee Name </td><td>Employee Address </td><td>Employee Resume </td><td>Employee Photo </td></tr>
<%
while(rs.next()){
%>
<tr>
<td><%=rs.getString(2)%> </td>
<td><%=rs.getString(3)%> </td>
<td><a href="Download.jsp?resumeId=<%=rs.getString(1)%>"> Download Here</a> </td>
<td><a href="Download.jsp?photoId=<%=rs.getString(1)%>"> Download Here</a> </td>
<%
}
%>
</table>
</body>

这是download.jsp

<body>
<%
String fileName="";
String querytext="";
ServletOutputStream op1= null;
byte barray[] =null;
Class.forName("com.mysql.jdbc.Driver");
Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql", "root", "admin");
if(request.getParameter("resumeId")!=null)
{
 querytext="select emp_resume from employeereg1 where emp_id="+request.getParameter("resumeId");
 }
 else{
 querytext="select emp_pic from employeereg1 where emp_id="+request.getParameter("photoId");    
 }
 PreparedStatement ps = conn.prepareStatement(querytext);
 ResultSet rs=ps.executeQuery();
 while(rs.next()) {
 fileName=rs.getString(1);
 }
 String mimetype=application.getMimeType(fileName);
 response.setContentType((mimetype != null) ? mimetype : "application/octet-stream");
 response.addHeader("Content-Disposition","attachment; filename="+fileName);
 Blob blb = rs.getBlob(1);
 byte[] bdata = blb.getBytes(1, (int) blb.length());
 OutputStream output =  response.getOutputStream();
 output.write(bdata);
 output.flush();
 output.close();
 %>
</body>

将显示此错误 严重：带有路径[/ DBFileDownload1]的上下文中servlet [jsp]的Servlet.service（）引发异常[在第63行处理JSP页面/Download.jsp时发生异常

60：response.setContentType（（mimetype！= null）？mimetype：“application / octet-stream”）; 61：response.addHeader（“Content-Disposition”，“attachment; filename =”+ fileName）; 62：//从Blob创建字节数组 63：Blob blb = rs.getBlob（1）; 64：byte [] bdata = blb.getBytes（1，（int）blb.length（））; 65： 66：//获取响应输出流对象，将文件内容写入标题

Stacktrace：]有根本原因 java.sql.SQLException：结果集结束后` 在com.mysql.jdbc.SQLError.createSQLException（SQLError.java:910）在com.mysql.jdbc.ResultSet.checkRowPos（ResultSet.java:726）在com.mysql.jdbc.ResultSet.getBlob（ResultSet.java:1416）在org.apache.jsp.Download_jsp._jspService（Download_jsp.java:157）

我想使用jsp从mysql数据库下载doc文件和图像

0 个答案: