/**
 * A real Singleton we want to have
 */
public class SubSingletonB extends SingletonB {
 public static boolean instanceFlag = false; //true if 1 instance
 //private int i = 0;
 
 public SubSingletonB() throws SingletonExecption {
 if(instanceFlag) {
 throw new SingletonExecption("Only can create a instance !");
 } else {
 instanceFlag = true;
 super.Register("Sub1", this);
 }
 }
 
 public void finalize() {
 instanceFlag = false;
 }
}