image4.jsp

一本jsp自学教材

<%@ page contentType="text/html;charset=gb2312"%>   
<%@ page import="java.sql.*"   %>   
<%@ page import="java.util.*"%>    
<%@ page import="java.text.*"%>   
<%@ page import="java.io.*"%>   
<%
  String pid=request.getParameter("id");
  String driverName="com.mysql.jdbc.Driver";
  String username="root";
  String password="yesterdayn";
  String dbName="study";
  String tableName="roles";
  try{ 
  Class.forName("com.mysql.jdbc.Driver");
  //建立同数据库的连接对象
   String url="jdbc:mysql://localhost/"+dbName+"?characterEncoding=GBK";
  Connection conn=DriverManager.getConnection(url,username,password);
String sql="SELECT image FROM "+tableName+" WHERE id="+pid;     
Statement stmt=null;   
ResultSet rs=null; 
ServletOutputStream sos=null;  
stmt=conn.createStatement();   
rs=stmt.executeQuery(sql);   

while(rs.next()){   
   response.setContentType("image/jpeg");   
   sos=response.getOutputStream();   
   InputStream is=rs.getBinaryStream("image");   
   byte b[]=new byte[0x7a120];   
   for(int i=is.read(b);i!=-1;)   
    {   
      sos.write(b);   
      is.read(b);   
    }   
   sos.flush(); 
  } 
sos.close(); 
}   
catch(Exception e)
{
System.out.println(e.toString());
}   
%>