private void checkIfStale(long ov){
synchronized (staleIoSet) {
    boolean removed=staleIoSet.remove(ov);
    if (removed) {
      unsafe.freeMemory(ov);
    }
  }
}

private void checkIfStale ( long ov ) { synchronized ( staleIoSet ) { boolean removed = staleIoSet . remove ( ov ) ; if ( removed ) { unsafe . freeMemory ( ov ) ; } } }
checks if the given overlapped is stale and if so , releases it .
