How do I download a file using JSP

[Amit Roy]

hello
Suooose i am displaying a list of file name in a JSP page and want that the user should be able to download the file as soon as he clicls on it how do i do it
Amit

[sudesai]

Hi Amit,
You would need to trap that filename in a variable, and then use the java.io.FileInputStream to display its contents.

<%@page import="java.io.*" %> 
<%! FileInputStream fin= null; %> 
<%! String fname = null; %>
<!- Note the  [I] filename [/I] is obtained from the user  clicking the name of the file in the list.It can be obtained by using the JSP implicit [I] request [/I] object -->
<%
  fname = request.getParameter("fileName");
  fin = new FileInputStream(fname);
  int i = 0;
  while ((i = fin.read()) != -1) {
     out.write(i);
  }
  out.flush();
%>

Hope this helps.
Regards,

[sudesai]

Hi Amit,
One more thing, that I owl like to mention.In case, your files are huge, then it would be advisable to use java.io.BufferedInputStream.
You just need to change the code to :

<%@page import="java.io.*" %> 
<%! FileInputStream fin= null; %> 
<%! BufferedInputStream bin = null; %>
<%! String fname = null; %>
<!- Note the   filename  is obtained from the user  clicking the name of the file in the list.It can be obtained by using the JSP implicit  request  object -->
<%
  fname = request.getParameter("fileName");
  fin = new FileInputStream(fname);
  bin = new BufferedInputStream(fin);
  int i = 0;
  while ((i = fin.read()) != -1) {
     out.write(i);
  }
  out.flush();
%>

Hope this helps,
------------------
Sandeep Desai

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[Amy Hafer]

In my case, reading and then writing the fileinputstream actually dumps a bunch of binary characters from the file to a new html page with a URL of the location of the servlet.
Has anyone else experienced this problem??

[maha anna]

Did you setup the response header properly? response.setContentType("application/pdf"); //Just an example
regds
maha anna