public void removeListener(Listener listener){
  queue.remove(listener);
  long casFrequency;
  while ((casFrequency=currentScheduledFrequency.get()) > 0 && queue.isEmpty()) {
    if (currentScheduledFrequency.compareAndSet(casFrequency,-1)) {
      break;
    }
  }
}

public void removeListener ( Listener listener ) { queue . remove ( listener ) ; long casFrequency ; while ( ( casFrequency = currentScheduledFrequency . get ( ) ) > 0 && queue . isEmpty ( ) ) { if ( currentScheduledFrequency . compareAndSet ( casFrequency , - 1 ) ) { break ; } } }
remove listener to validation list .
