Download and extract jar file from applet

Question

Can any one provide me a solution for my below problem. Thanks in advance for all the suggestions.
I want my applet to download a jar file, extract into users home directory by creating a folder and then set the created folder to java library path.
My applet html file is in "root" directory. The applet is included into applet.jar and placed under "lib" directory which is under "root" directory.
Now i also had another jar file(contains dlls what I packed) under the same lib folder.
The below is the following directory structure in my server.
root ---
     |
     |
     default.html
     lib--
     |
     |
     applet.jar - contains applet related classes
     native.jar - contains dlls which are to be loaded
When a client downloads my applet, it should copy the native.jar and then extract into a new folder under user home directory. Then set this folder to java library path.
Regards
raman kumar

Answer 1

I managed to do it this way, Just remember that you need to sign the jar files for your applet, else it won't work.
package jar.extract;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.jar.JarFile;
import java.util.zip.ZipEntry;
public class JarExtractor {
     // Dll file in the jar
     private static String JAR_FILE = "dll.jar";
     public void extract() {
          try {
               JarFile jf = new JarFile(JAR_FILE);
               // Entry in the jar file rember package and dll file
               ZipEntry ze = new ZipEntry("package/dll_file");      
               int length = (int) ze.getSize();
               byte fileContent[] = new byte[length];
               InputStream fin = jf.getInputStream(ze);
               fin.read(fileContent, 0, length);
               // CODE missing.
               // You need to write the input stream (fin) to a new files output stream
               // it is like copying a file !!!
          } catch (IOException e) {
               e.printStackTrace();
}Tom