Downloading a file in Java

Hello,
I would like to write a Java application to download some files from the Internet.
I have a basic understanding of Sockets with Perl. However, I have not done this in Java.
I would like to connect to a file on the Internet via a Socket and copy the file to my local machine.
I have browsed for tutorials on the Internet but have not found anything dealing with this (as mostly all information deals with downloading the JVM and such).
I can code it myself as I am not looking for a solution. However, I am looking for some basic pointers to get started. I was hoping someone could give me a list of classes I would need, a few urls to some nice tutorials or even some very basic code examples. Again, I just need to be pointed in the right direction to get started.
Thank you in advance!
Cheers,
Chris

Wouldnt it be possible for example "protect" the
server using username and password? For example the
URL could be:
http:\\www.mywebsite.com\my_upload_page.html?password=m
password&username=myusername
or something like that??Sure; but instead of passing clear-text usernames and passwords on the URL, the usual convention is to use encrypted authentication (ranging from BASIC authentication to CERTIFICATE authentication, where the authentication is put into the HTTP request body and encrypted at some level). But it of course still requires that the server be running some special servlet/application to accept the upload requests (hence the servlet/FTP hint).
That's all I'm going to say about it; it can be far too much a topic for discussion here and I don't want to spend all that much time on it.

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Downloading a File with Java

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The behaviour I would like (and indeed had until I upgraded to WInXp
Pro) is for the application to prompt the user to connect to the
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try {
//put your statement here
} catch(<TheException that is thrown>)
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next part of code
u can also use a finally block if u want that a
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Hi,
Please can u send me a sample code to upload a file and to download the same file from a remote server using a java servlets. The file should be read byte by byte.
Message was edited by:
user461713

Hi, Thank u.
Sorry, I forgot to attach a code. Here it is.
Actually i need to upload a file to a remote server and download it from a server to my machine. I'm trying it using servlets and using tomcat5.0 as a servlet container. Here i'm sening a code used to upload a file. Let me know whether it works. Only few lines are here.
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.lang.Object;
import java.util.*;
import java.lang.String;
import com.oreilly.servlet.MultipartRequest;
public class FileUpload extends HttpServlet{
     public void doPost(HttpServletRequest req, HttpServletResponse res)throws
     ServletException, IOException{
     MultipartRequest multi=new MultipartRequest(req);
     String file="file1";
     byte[] b=file.getBytes();
     InputStream in=null;
     BufferedInputStream bis=null;
     FileWriter fw=null;
try{
     in=multi.getInputStream("file1");
bis=new BufferedInputStream(in);
     File output=new File("/fileuploadtest");
     fw=new FileWriter(output);
          int i;
          i=bis.read();
          while (i != -1) {
fw.write(i);
i = bis.read();
     catch(IOException e){
          System.out.println("Exception=" +e);
finally{
     try{
          if(in!=null)
          in.close();
          if(bis!=null)
          bis.close();
          if(fw!=null)
          fw.close();
     catch(Exception e){
          System.out.println(e);
This code is giving error as: cannot resolve symbol: class MultipartRequest
Why is this happening?
Pls let me know whether this code works or no and also i have written form.html.
Can u pls tel me whether there are ways in which i can write a code to upload a file using servlets without using third party packages. Pls help.
Also how should be the servlet mapping for this code.?
Regards
Message was edited by:
user461713

How to Download a file from web server using servlets

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http://otn.oracle.com/sample_code/tech/java/sqlj_jdbc/files/advanced/advanced.htm
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Please post your code using code tags (click on CODE above the text area, when posting)
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