code: @SuppressWarnings("SynchronizationOnLocalVariableOrMethodParameter")
  	protected final Buckets getOrCreateBuckets(Stopwatch stopwatch) {
  		synchronized (stopwatch) {
  			Buckets buckets = getBuckets(stopwatch);
  			if (buckets == null) {
  				buckets = createBuckets(stopwatch);
  				stopwatch.setAttribute(ATTR_NAME_BUCKETS, buckets);
  			}
  			return buckets;
  		}
  	}
docs: Returns the buckets attribute or create it if it does not exist.