Display download window from JSP

Question

Hi,
I hava a links to PDF files on a JSP. These PDF files are not in the web server virtual path. When user clicks a link in the browser then it should display download or open from current location window. How can I do this. Please help me.
Thanks,
Simi

Answer 1

The following code you post the complete filepath to a servlet
Recommendations:
Replace the filepath by a pointer to a session-variable or database-entry
by which you can dynamicaly retrieve and keep the full path on the serverside.
Code:
in your for jsp insert:
use &lt;a href="#" onClick="downloadform.FILENAME.value="<%= your dynamic path here %>">download &lt;%= your dynamic path here %>&lt;/a>
&lt;form method=post name=downloadform action="servlet/DownloadServlet">
&lt;input type=text name=FILENAME>
&lt;input type=submit value="get file">
&lt;/form>
&lt;/html>
* Class : DownloadServlet
* function :
* create an file outputstream
* Usage :
* create an file outputstream
* doGet is functionally disabled
* to hide parameters from the adressbar
* Date : 05-03-2002
* By : [email protected]
import java.io.*;
import java.net.*;
import java.util.*;
import javax.servlet.http.*;
import javax.servlet.*;
public class DownloadServlet extends HttpServlet {
public void init(ServletConfig config) throws ServletException {
super.init(config);
protected void doGet( HttpServletRequest request
, HttpServletResponse response) throws ServletException
, IOException {
StringBuffer sb = new StringBuffer();
ServletOutputStream out = response.getOutputStream();
sb.append("Sorry, getter method is no longer supported\n");
protected void doPost( HttpServletRequest request
, HttpServletResponse response) throws ServletException
, IOException {
ServletOutputStream out = response.getOutputStream();
ServletContext context = this.getServletConfig().getServletContext();
HttpSession session = request.getSession();
String file = "";
StringBuffer sbe = new StringBuffer();
file = request.getParameter("FILENAME");
String fileName = file.substring(file.lastIndexOf("\\")+1); // Windows
String fileName = file.substring(file.lastIndexOf("/")+1); // UNIX or Linux
String fileName = file.substring(file.lastIndexOf("\\")+1);
File downloadfile = new File(file);
long filesize = downloadfile.length();
if ( !downloadfile.exists() ) {
sbe.append( "<p style='color:#000080;font-family:arial'>");
sbe.append( "<b>The system cannot find file <i>'" + fileName + "'</i></b><br>" );
sbe.append( "<b>It may have been (re)moved</b><br>" );
sbe.append( "Contact you administrator for information" );
sbe.append( "</p>");
out.print(sbe.toString());
} else {
try {
// Read the file requestparameter.
// This should be a file relative to the directory
int lastDot = file.lastIndexOf(".");
String ext = file.substring(lastDot+1).toLowerCase();
String contenttype = "text/html"; // DEFAULT CONTENTTYPE
contenttype = "application/octet-stream";
response.setHeader("Content-Disposition", "attachment; filename=" + fileName + ";");
response.setHeader("Cache-Control", "Pragma");
response.setContentType(contenttype);
response.setContentLength((int)filesize);
BufferedInputStream bis = new BufferedInputStream(new FileInputStream(file));
BufferedOutputStream bos = new BufferedOutputStream(out);
// stream the file back to the client
byte[]buffer = new byte[1024];
int size;
size= bis.read(buffer);
while ( size != -1 ) {
bos.write( buffer, 0, size );
size = bis.read(buffer);
bis.close();
bos.flush();
} catch ( Exception e ) {
response.reset();
response.setContentType("text/html");
sbe.append("<h1 style='color:#800000;font-family:arial'>Error:</h1>");
sbe.append( "<p style='color:#000080;font-family:arial'>");
sbe.append( "<b>An error occured while trying to retrieve <i>'" + fileName + "'</i></b><br>" );
sbe.append( "Contact you administrator for information" );
sbe.append( "</p>");
out.print(sbe.toString());