COmpressing files and folders in Java

[msankardas]

Hi,

As a part of my project, i need to compress folders and files into a single zip file as follows.

for eg:
I want to compress
C:\test\
c:\compression\
C:\documents\test.txt

all of these into a single zip file... I need to maintain the folder structure as well, when i unzip them using WINZIP.

I am able to compress each of them seperately, but not together...I am making use of java.util.zip.*;

Is there anyway to append more files to an existing zip file??? i am a bit confused with the input and output streams now!!!

Urgent help required.

Thanks in advance..

My code is as follows: [I am open to all suggestions!!!]

import java.io.*;
import java.util.zip.*;
 
public class ZipCreateExample {
    static ZipOutputStream cpZipOutputStream = null;  
         String[] strSource=new String[3];
         static String strTarget = "";
          String strSubstring = "";
 
 
         public static void main(String[] args) throws IOException 
    {
     System.out.println("Example of ZIP file creation.");
 
     // Specify files to be zipped
     String[] filesToZip = new String[3];
     filesToZip[0] = "C:\\compress.java";
     filesToZip[1] = "C:\\test.txt";
     filesToZip[2] = "C:\\Compresstest";
 
     int n=filesToZip.length;
 
     // Specify zip file name
     String zipFileName = "c:\\example2.zip";
 
     ZipCreateExample udZipUtility = new ZipCreateExample();
 
        for(int i=0;i<n;i++)
 
            udZipUtility.strSource[i] = filesToZip[i];
            udZipUtility.strTarget = zipFileName;
 
            udZipUtility.zip(filesToZip,n);
 
 
           cpZipOutputStream.close();
           System.out.println("\n Finished creating zip file " + strTarget + " from source ");
    }
 
   private void zip(String[] filesToZip, int n){
        try
        {  ///int count=0;
            for(int i=0;i<n;i++)
            {
               File cpFile = new File(filesToZip[i]);
               System.out.println(filesToZip[i]);
               if (!cpFile.isFile() && !cpFile.isDirectory() ) {
                System.out.println("\nSource file/directory Not Found!");
                return;
            }
            if  (cpFile.isDirectory()) {
                strSubstring = strSource[i];
            } else {
                strSubstring = "";
            }
            String zipFileName = "c:\\example2.zip";
            //count=count+1;
            cpZipOutputStream = new ZipOutputStream(new FileOutputStream(zipFileName));
            cpZipOutputStream.setLevel(9);
            zipFiles(cpFile);
 
            //cpZipOutputStream.finish();
            //cpZipOutputStream.close();
            //System.out.println("\n Finished creating zip file " + strTarget + " from source " + strSource);
        }
        //cpZipOutputStream.finish();
        cpZipOutputStream.close();
        //System.out.println("\n Finished creating zip file " + strTarget + " from source ");
        }
        catch (Exception e){
            e.printStackTrace();
        }
 
}
 
private void  zipFiles(File cpFile) {
 
    if (cpFile.isDirectory()) {
        File [] fList = cpFile.listFiles() ;
        for (int i=0; i< fList.length; i++){
            zipFiles(fList[i]) ;
        }
    } else {
        try {
            String strAbsPath = cpFile.getAbsolutePath();
            String strZipEntryName ="";
            if (!strSubstring.equals("") ){
                strZipEntryName  = strAbsPath.substring(strSource.length+1, strAbsPath.length());
            } else {
                strZipEntryName  = cpFile.getName();
            }
 
            byte[] b = new byte[ (int)(cpFile.length()) ];
            FileInputStream cpFileInputStream = new FileInputStream (cpFile) ;
 
            ZipEntry cpZipEntry = new ZipEntry(strZipEntryName);
 
//             Add ZIP entry to output stream.
            cpZipOutputStream.putNextEntry(cpZipEntry );
            //int i = cpFileInputStream.read(b, 0, (int) cpFile.length());
 
            cpZipOutputStream.write(buffer,0,cpFileInputStream.read(buffer));
            /*
            int len;
            while ((len = cpFileInputStream.read(b)) > 0)
            {
                cpZipOutputStream.write(b,0,len);
           }
            cpZipOutputStream.closeEntry();
 
            //cpZipOutputStream.putNextEntry(cpZipEntry );
 
            //cpZipOutputStream.write(b, 0, (int)cpFile.length());
 
            //cpFileInputStream.close();
 
 
            */
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
 
}
}

[JosAH]

That for loop 'for (int i= 0; i < n; i++)' in your main method really looks suspicious.
You really should fix your indentation and you really should split things up in small
coherent methods. The little Zip framework is really easy: open a ZipOutputStream,
add ZipEntries and their content and close the entire thing again. Next you open
a ZipFile, read the entries that are in it and read them.

kind regards,

Jos

[msankardas]

That for loop 'for (int i= 0; i < n; i++)' in your main method really looks suspicious.
You really should fix your indentation and you really should split things up in small
coherent methods. The little Zip framework is really easy: open a ZipOutputStream,
add ZipEntries and their content and close the entire thing again. Next you open
a ZipFile, read the entries that are in it and read them.

kind regards,

Jos

sorry abt the indentation... i think the logic which i used is wrong here.
regarding the zip, i am able to zip a particular file or folder, but the problem arises for the selective zip part.. only the final one gets zipped in the output. the other 2 entries are overwritten by the final entry.

is it possible to get all the files and folders in a buffer, keep the stream open as each and every file and directory is inserted into the buffer and then zip the whole thing in one go???

[msankardas]

sorry abt the indentation... i think the logic which i used is wrong here.
regarding the zip, i am able to zip a particular file or folder, but the problem arises for the selective zip part.. only the final one gets zipped in the output. the other 2 entries are overwritten by the final entry.

is it possible to get all the files and folders in a buffer, keep the stream open as each and every file and directory is inserted into the buffer and then zip the whole thing in one go???

I am able to compress properly now.. was having a small error in the streaming and in the calling of the files. Like u said, my for loop was creating some problems... fixed it now..
THanks A LOT!!!