import java.net.JarURLConnection;
import java.net.URL;
import java.util.jar.JarEntry;
public class Main {
public static void main(String[] argv) throws Exception {
URL url = new URL("jar:file:/c://my.jar!/");
JarURLConnection conn = (JarURLConnection) url.openConnection();
JarEntry jarEntry = conn.getJarEntry();
}
}