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Multipart Upload - where does my file go?

Dave Donohoe
Ranch Hand

Joined: May 16, 2000
Posts: 73
Hi all,
I have a servlet that uses Multipart requests to upload files.
I am running tomcat3.2 as my webserver. I want to upload a file from my C: drive to the Web Server. I create a multipart request in the servlet like so -
MultipartRequest multi = new MultipartRequest(req, "e:\\temp", 5 * 1024 * 1024);
However, when I run the servlet, it does not put the file into the folder I specified......what am I doing wrong?
Mike Curwen
Ranch Hand

Joined: Feb 20, 2001
Posts: 3695

But what *does* it do?

If you surround the code with try-catch, what does the thrown exception report? Does it not throw an exception? Does it put the file somewhere else?
Dave Donohoe
Ranch Hand

Joined: May 16, 2000
Posts: 73
Hi there Mike,
Let me explain a bit better. I have a servlet called UploadTest & This is called from a HTML Form.
At the top of this HTML Form I have the following -
<form method="post" action="..\UploadTest" name="Box" ENCTYPE="multipart/form-data">
<input type="file" name="hello">
This places a Text Box & a browse button on the form (which I did not notice yesterday as it was behind other components).
When I hit browse & select a file it uploads the file as expected. But, I dont want to give the user the option to select the file as I want to hardcode the name of the file in the code.
How do I do this?
This is the servlet code -
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import com.oreilly.servlet.MultipartRequest;
public class UploadTest extends HttpServlet {
public void doPost(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
PrintWriter out = res.getWriter();

try {
// Blindly take it on faith this is a multipart/form-data request
// Construct a MultipartRequest to help read the information.
// Pass in the request, a directory to save files to, and the
// maximum POST size we should attempt to handle.
// Here we (rudely) write to the server root and impose 5 Meg limit.
MultipartRequest multi = new MultipartRequest(req, "e:\\temp", 5 * 1024 * 1024);

// Print the parameters we received
Enumeration params = multi.getParameterNames();

while (params.hasMoreElements()) {
String name = (String)params.nextElement();
System.out.println("~~" + name);
String value = multi.getParameter(name);
out.println(name + " = " + value);
// Show which files we received
Enumeration files = multi.getFileNames();
while (files.hasMoreElements()) {
String name = (String)files.nextElement();
System.out.println("NAME - " + name);
String filename = multi.getFilesystemName(name);
System.out.println("FILENAME - " + filename);
String type = multi.getContentType(name);
System.out.println("TYPE - " + type);
File f = multi.getFile(name);
out.println("name: " + name);
out.println("filename: " + filename);
out.println("type: " + type);
if (f != null) {
out.println("length: " + f.length());
catch (Exception e) {

Basically, I want to be able to upload files without any direct interaction from the user.
I agree. Here's the link:
subject: Multipart Upload - where does my file go?
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