void scheduleWrite(Message m) {
    q.add(m);
    if (!isScheduled.getAndSet(true)) {
      executor.submit( this);
    }
  }
void scheduleWrite(Message m) {
    q.add(m);
    if (!isScheduled.getAndSet(true)) {
      executor.submit( this);
    }
  }
void scheduleWrite ( Message m ) { q . add ( m ) ; if ( ! isScheduled . getAndSet ( true ) ) { executor . submit ( this ) ; } }
put a message on the queue, schedule writing if not already scheduled.
put a message on the queue schedule writing if not already scheduled .