Compression program in java

hello all,
any idea how to write a file compression program in java.
any help would be appreciated.
thanx

The same way you would write a compression program in any other language.
Open a stream for the file to be compressed
Open a stream for the compressed file, add a filter-stream (according to your choice of algorithm) to the stream for the compressed file.
Read from one stream, write to the other.
For uncompressing, reverse the above. :)
With java you have some small addenums that are useful, like the java.util.zip classes if it is basic zip-functionality that you want.
Once all this is done, as sugar on the top, fix a nice gui involving JTable, JTree and other eminent swing-components of your choice.
A fair bit of warning, if you want to use the JFileChooser for your logical file-view inside a compressed file, you are in for a ride. You will have to make your own FileView and File object. The java.io.File object is badly designed and it will be a long hassle to make it work, but it can be done.
Yours sincerely
Peter Norell

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File Compression program in java

hello all,
any idea how to write a file compression program in java.
any help would be appreciated.
thanx

import java.io.*;
import java.util.zip.*;
import java.io.File;
import java.io.FileInputStream;
import java.util.zip.CRC32;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
import java.util.Date;
import java.util.Vector ;
public class FileZip
     //Creating Constructor to pass the vector
     Vector v;
     public FileZip(Vector v, JavaUpload applet){
          this.v = v;
     //Creating Constructor to pass one file
     public FileZip(File file){
          v.addElement(file);
     //default constructor
     public FileZip(){
     public void addFile(File file){
          v.addElement(file);
     public void removeFile(File file){
          v.removeElement(file);
     ByteArrayOutputStream out;
     //This method helps to zip the files
     public ByteArrayOutputStream doJob(){
               try {
               out = new ByteArrayOutputStream();
               ZipOutputStream zout = new ZipOutputStream(out);
               zout.setMethod(ZipOutputStream.DEFLATED);
                    for (int i=0; i < v.size(); i++){
                    File file = new File (((File)(v.elementAt(i))).getPath());
               byte [] rgb = new byte [1000];
               int n;
               FileInputStream fis;
          //Calculate the CRC-32 value.
               CRC32 crc32 = new CRC32();
               fis = new FileInputStream(file);
               while ((n = fis.read(rgb))>-1){
               crc32.update(rgb, 0, n);
               fis.close();
          //create a zip entry
               ZipEntry zipentry = new ZipEntry(file.getName());
               zipentry.setSize(file.length());
               zipentry.setTime(file.lastModified());
               zipentry.setCrc(crc32.getValue());
          //Add the zip entry and associated data
               zout.putNextEntry(zipentry);
               fis = new FileInputStream(file);
               while ((n= fis.read(rgb))>-1){
               zout.write(rgb,0,n);
               fis.close();
               zout.closeEntry();
               zout.close();
          }catch(ZipException ze){}
          catch(IOException ioe){}
          return out;

When i click on the Firefox icon I get an error message, C:\Program Files\Java\jre6\lib\deploy\jqs\ff\..\..\..\..\bin\jqsnotify\.exe cannot be found. What is it? and how do i fix it? in English

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{color:#000000}Hello,
i am in great trouble someone please help me. i want to execute java program through java code i have compiled the java class using Compiler API now i want to execute this Class file through java code please help me, thanks in advance
{color}

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mahesh

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New "Windows Programming Using Java" Website

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[email protected] and [email protected]
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Hi, I am looking the similar kind of requirement that you had done.. Do you have any more details on the code that is working for you . All i need is if the user logs in successfully in windows, the the app should be accessible. Please let me know if you have the code with you on this problem.
Thanks in advance
"what i meant is the we b applications running in my system, when i access the application iam able to to login automatically with windows authentication and now in case of other users following process happened:"

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>
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>
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I have a class "Stimulus.java" in which another jar's class has been used. When I created jar and executed I got below error. I used "-classpath" to set dependancy jar file. Any clues are appreciated.
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        at Stimulus.main(Stimulus.java:4)

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F:\Tomcat5\webapps\Ambika\WEB-INF\Classes>
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Compression program in java

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