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downloading image

Greenhorn

Posts: 10

posted 22 years ago

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hi
i am unable to see image after downloading.file is downloading..
i am doing this in jsp.
help me my code is..
user=request.getParameter("user");
filename=request.getParameter("path");
response.setContentType("application/x-filler");
try
{
String downloadFile = "/usr/tomcat/webapps/ap123/users/"+user+"/"+filename;
response.setHeader("Content-Disposition","attachment;filename="+filename);
BufferedInputStream fif = new BufferedInputStream(new FileInputStream(downloadFile));
int data;
int i = 0;
while((data = fif.read()) != -1)
{
out.print((char)data);
// flushBuffer();

}
fif.close();
}
catch(Exception e) { e.printStackTrace(); }
thanks
pravi

William Brogden

Author and all-around good cowpoke

Posts: 13078

posted 22 years ago

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I already told you this in the servlet area!
JSP is designed to send characters. Your code is sending characters where the browser expects binary. Images must be sent in binary, therefore you should be using a servlet to handle image requests.
Didn't you believe me or what???
I just can not understand why people will keep doing this. There is no reason to be afraid of servlets - servlets are your friends.
Bill

pravallika reddy

Greenhorn

Posts: 10

posted 22 years ago

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hi Bill!!
thanks...i believe u..
then how to include servlet in my jsp file and how to set content type in servlet..
please let me..
thanks in adv
pravi

Originally posted by William Brogden:
I already told you this in the servlet area!
JSP is designed to send characters. Your code is sending characters where the browser expects binary. Images must be sent in binary, therefore you should be using a servlet to handle image requests.
Didn't you believe me or what???
I just can not understand why people will keep doing this. There is no reason to be afraid of servlets - servlets are your friends.
Bill

William Brogden

Author and all-around good cowpoke

Posts: 13078

posted 22 years ago

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Your JSP must generate HTML that contains an <IMG tag that points to a servlet. The servlet is not part of the JSP, but is part of the "web application" that the JSP belongs to. Any servlet book (mine included) can show you how to do this.
Here is an example of an image serving servlet - which has some hard-coded file locations.

// Random image server
package com.JSPbook.Chap04;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class ImgServA extends HttpServlet
{
  static String basePath = "c:\\tomcat\\webapps\\Root\\JSPbook\\Chap04\\images";
  static String[] pics = {
     "Minnie.gif","Charmer.gif","Frieda.gif","Rufus.gif","Vita.jpg"
  };
  static String errorPic = "Sorry.gif";
public void init(ServletConfig config) throws ServletException {
super.init(config);
    System.out.println("ImgServ initialized");
// In a real application, we would read in the picture file list
}
public void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException
{
  ServletContext sctx = getServletContext();
  String path = req.getPathInfo();
  String que = req.getQueryString();
  System.out.println("path info " + path + " query: " + que );
  int select = -1 ;
  float ranf ;
  String image = req.getParameter("RandomImage");
  try {
      ranf = new Float( image.trim() ).floatValue(); 
  select = (int)(ranf * pics.length ); // 0 - n-1
}catch(Exception e0 ){
    select = 0 ;
}
  File f = new File( basePath, pics[select] );
  int sze = 0;
  byte[] buf ;
  try {
      sze = (int)f.length(); // throws IOException if no file  
  if( sze < 1 ){
     f = new File( basePath, errorPic );
     sze = (int)f.length();
  }
    buf= new byte[ sze ];
    String type = "image/gif" ;
    if( f.getAbsolutePath().endsWith("jpg")) type = "image/jpg";
  resp.setContentType( type );
  resp.setContentLength( sze );
  OutputStream out = resp.getOutputStream();
      RandomAccessFile raf = new RandomAccessFile( f, "r" );
      raf.read( buf );
      raf.close();
  out.write(buf);
  out.close();
}catch(Exception ex ){
  System.err.println("ImgServletA throws " + ex );
  ex.printStackTrace( System.err );
}
}
}

And here is the JSP page that calls that servlet.

Bill

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