[java] Downloading and extracting files with Java

Hi, i'm not sure of your exact requirements but would this be a task better suited to a script of some kind (perl etc..) or do you have to use java?

Well, now that I think of it, I guess I could use a script.
I have a Java program that uses some files. However, I want the files to be up to date all the time. So every few hours, I need a program to download the newest files and unzip them.
I figured I'd do it in Java, since that's what the other program is written in.

However, I didn't really consider doing it in another scripting language.

I'm very familiar with Java, but sadly I'm not very experienced with scripting languages.

Do you have any pointers?

Thanks again!

If the file is available publicly, then you can just open a URLConnection to the file and download it that way. You can then use the java.util.zip package to unzip it.

Interesting, Jester.
I'll look into that.

Thanks a bunch for the tips. You both really helped me find a place to start.

I've been able to download the files... I got that part working.
I'm unable to unzip them though.

Apparantly the normal ZipFile classes aren't of use for me. The archives I need to extract are actually .tgz files.

Anybody have pointers on how to extract the .tar files from the .tgz files?

Thanks again for any help.

*EDIT* I've got it to work now.
Thanks to everyone for helping me.

[Edited by - ShauwnBlue on July 7, 2008 6:15:43 PM]

I would use the command line to unzip the files once you have them downloaded. You can do this from your Java program by using Runtime.getRuntime().exec(unzipCommandString);

Make sure you have the absolute path of the zip file and destination folder it will make things more robust than attempting to navigate the runtime to the right directory. I would use the unix command gunzip if you're working on a unix based operating system.

Here's just a quick link I found for the gunzip command GZIP

If your on a windows machine then I would use winrar or winzip.

Heres a link of how to use winrar through the command prompt on a windows machine.
http://www.respower.com/page_tutorial_unrar


Good Luck hope this helps.

Thanks very much for taking the time to write up that response with links and everything. I appreciate it.
It was very helpful as well.