hi ther...
hope this code wil help u....
this is for creating jar file
import java.io.*;
import java.util.*;
import java.util.jar.*;
public class JarCreate {
public static void main(
String[] args) throws IOException {
// Create the jar file, using the first command line argument as the
// file name (clobbering the file if it exists).
String jarName = args[0];
JarOutputStream jar = new JarOutputStream(new FileOutputStream(jarName), new Manifest());
System.out.println(jarName + " created.");
try {
// Allocate a buffer for reading the input files.
byte[] buffer = new byte[1024];
int bytesRead;
// Loop through the file names provided on the command-line.
for (int i = 1; i < args.length; i ++) {
// Get the file name.
String fileName = args[i];
try {
// Open the file.
FileInputStream file = new FileInputStream(fileName);
try {
// Create a jar entry and add it to the jar.
JarEntry entry = new JarEntry(fileName);
jar.putNextEntry(entry);
// Read the file the file and write it to the jar.
while ((bytesRead = file.read(buffer)) != -1) {
jar.write(buffer, 0, bytesRead);
}
System.out.println(entry.getName() + " added.");
} catch (Exception ex) {
System.out.println(ex);
}
finally {
file.close();
}
} catch (IOException ex) {
System.out.println(ex);
}
}
} finally {
jar.close();
System.out.println(jarName + " closed.");
}
}
}
this is for extracting jar files
import java.io.*;
import java.util.*;
import java.util.jar.*;
public class JarExtract {
public static void main(String[] args) throws IOException {
// Get the jar name and the entry name.
String jarName = args[0];
String entryName = args[1];
// Open the jar.
JarFile jar = new JarFile(jarName);
System.out.println(jarName + " opened.");
try {
// Get the entry and its input stream.
JarEntry entry = jar.getJarEntry(entryName);
// If the entry is not null, extract it. Otherwise, print a
// message.
if (entry != null) {
// Get an input stream for the entry.
InputStream entryStream = jar.getInputStream(entry);
try {
// Create the output file (clobbering the file if it exists).
FileOutputStream file = new FileOutputStream(entry.getName());
try {
// Allocate a buffer for reading the entry data.
byte[] buffer = new byte[1024];
int bytesRead;
// Read the entry data and write it to the output file.
while ((bytesRead = entryStream.read(buffer)) != -1) {
file.write(buffer, 0, bytesRead);
}
System.out.println(entry.getName() + " extracted.");
} finally {
file.close();
}
} finally {
entryStream.close();
}
} else {
System.out.println(entryName + " not found.");
} // end if
} finally {
jar.close();
System.out.println(jarName + " closed.");
}
}
}
any doubts dont hesitate to mail me back
Rao