java URL file download

Question

I am trying to create a java console app which will download a file from a URL. The file is created at Runtime and I don't know the file name. When I copy and paste the URL in the browser the save file pop up comes up to save the file. Now I want to create Java code which logs on to the server (validates user I have that done) go to that URL and download the file.

Sorry My question is how to implement this. I wrote code like below and when I run it it returns the HTML code instead of the actual .xlsx file. I need to change the code so that when the URL is accessed by my app. The report will be generated and returned at which point I will save the file to the local machine — Mohamed, Jun 13 '12 at 16:34
As one might expect, there have been **many** questions about how to programmatically download files from a server in Java, such as [How do you Programmatically Download a Webpage in Java](http://stackoverflow.com/questions/238547/how-do-you-programmatically-download-a-webpage-in-java). Voting to close this as a duplicate (please feel free to suggest a more canonical duplicate if you know of one). — Andrzej Doyle, Jun 13 '12 at 16:38
Andrzej that is what I am getting now. What I want is the file that is created when the URL is accessed — Mohamed, Jun 13 '12 at 16:40

score 1 · Answer 1 · answered Jun 13 '12 at 16:35

1

Sergii's answer is a good start; however, if the website you want to use requires more that a simple download, consider using Apache's HttpClient.

It supports cookies, authentication, URIs as well as URLs, and file upload.

answered Jun 13 '12 at 16:35

Edwin Buck

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score 0 · Answer 2 · answered Jun 13 '12 at 16:29

0

Simple exapmple from docs, just to put your url insted of http://www.oracle.com/, and change System.out.println(inputLine); to write file on disk.

import java.net.*;
import java.io.*;

public class URLReader {
    public static void main(String[] args) throws Exception {

        URL oracle = new URL("http://www.oracle.com/");
        BufferedReader in = new BufferedReader(
        new InputStreamReader(oracle.openStream()));

        String inputLine;
        while ((inputLine = in.readLine()) != null)
            System.out.println(inputLine);
        in.close();
    }
}

answered Jun 13 '12 at 16:29

Sergii Zagriichuk

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Thanks Sergii but this will only return the HTML code at that page. – Mohamed Jun 13 '12 at 16:37
@Saned - This code will request a *resource* from the server, and will then download the stream of bytes that the server sends in response. So if the URL is for an HTML page you'll get HTML; if the URL points at a Zip file you'll get the bytes of that Zip file. I'm not sure what else you could want? – Andrzej Doyle Jun 13 '12 at 16:56
I have made some update the URL points to a form. I changed the code to post to that form. Once the post is completed a file should be generated. I want to download that file. – Mohamed Jun 13 '12 at 18:27
I've written put YOUR url, it means that you should handle moment of generation file, and put url DYNAMICALLY after file will be generated! – Sergii Zagriichuk Jun 13 '12 at 20:59

java URL file download

2 Answers2