sclass SingleThreadProfiler is AutoCloseable {
  // config
  settable Thread threadToSample = currentThread();
  settable int interval = poorMansProfiling_defaultInterval();
  
  // results
  new MultiSet<S> stackTraceMultiSet;
  gettable int samples;
  
  // temporary
  java.util.Timer timer;
  Lock lock = lock();

  void start {
    lock lock;
    stop();
    clear();
    timer = doEvery_daemon(interval, r {
      StackTraceElement[] stackTrace = threadToSample.getStackTrace();
      if (!isThreadRunnable_x(stackTrace)) ret;
      
      lock lock;
      samples++;
      results.add(stackTraceToString(stackTrace));
    });
  }

  public  void stop aka close() {
    lock lock;
    if (timer != null) {
      stopTimer(timer);
      timer = null;
    }
  }

  void clear() {
    lock lock;
    results.clear();
    samples = 0;
  }

  MultiSet<S> results() {
    ret stackTraceMultiSet;
  }

  MultiSet<S> stopAndGetResults() {
    lock lock;
    stop();
    ret results();
  }
}