Running Zipping Program from within JSP

Ok, here is the situation.  We have a website linked to a massive database (USDA).  Through the website the user can pair down this data to get a more refined data set.  For example, The user can see the reported losses report by corn farmers in Kansas for 2000 through 2003.  We want to allow the user to no only see the data in the browser, but to be able to save and download the data as a Comma Seperated Value (CSV) file.  Saving the file is failry simple and we have that worked out.  These files are huge, so we want to zip them after they are created to make downloads faster.  The only problem is I can't get teyh command line version of any zipping program (winzip, winrar, etc..) to run from inside JSP code.  Here is the code, please help if you have any ideas.

// the file is already created
Runtime rt = Runtime.getRuntime();
Process p = null;
try {
String[] cmd = {"winrar.exe A", "d:\\tomcat4\\webapps\\dashboard\\down.zip d:\\tomcat4\\webapps\\dashboard\\data.csv"};
 p = rt.exec(cmd);
p.waitFor();
} catch (Exception e)
{
e.printStackTrace();
}
sjnoAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

dyanetCommented:
Two other solutions for you:
1. use java.util.zip package to compress the files. Use FileInputStream to read the file in and ZipOutputStream to write it the output file.  You can probably do that while you are creating the CSV file for the first time.
2. If you are running behind Apache, investigate and see if mod_gzip will solve your problem.  Most modern browsers support compressed content and Apache will automatically compress the file to achieve the desired goal - less use of bandwidth.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
u9707118Commented:
Here is a pure java solution that I have written for my project.
You can play around with the 'BUFFER' size for performance.


import java.util.ArrayList;
import java.util.zip.*;
import java.io.*;

static final int BUFFER = 2048;
byte data[] = new byte[BUFFER];          

FileOutputStream dest = new FileOutputStream("c:\\mydata\\myZipFile.zip");
ZipOutputStream out = new ZipOutputStream(new BufferedOutputStream(dest));
BufferedInputStream origin;
ArrayList filenameList = new ArrayList();

filenameList.add("mycsvfile1.csv");
filenameList.add("mycsvfile2.csv");
//etc..

for (int counter=0; counter<filenameList.size(); counter++) {
            FileInputStream fi = new FileInputStream((String)filenameList.get(counter));
            origin = new BufferedInputStream(fi, BUFFER);
            ZipEntry entry = new ZipEntry((String)filenameList.get(counter)); //creates entry containing file
               
            entry.setMethod(ZipOutputStream.DEFLATED); //sets method to compressed
            out.putNextEntry(entry); //adds entry to zip file
       
            //write data to zip file
            int count;
            while((count = origin.read(data, 0, BUFFER)) != -1) {
                out.write(data, 0, count);
            }//end while
            origin.close();          
                 
}//end for
out.close();




Hey presto you have a compressed zip file that you can spit back to your user.

Hope this helps,

Damian
sjnoAuthor Commented:
If I knew how to split points I would but since dyanet answered first they gets the points I guess.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
JSP

From novice to tech pro — start learning today.