code: static synchronized boolean startSingleton(CloudWatchMetricConfig config) {
          if (singleton != null) {
              return false;
          }
          log.info("Initializing " + MetricCollectorSupport.class.getSimpleName());
          return createAndStartCollector(config);
      }
docs: Starts a new CloudWatch collector if it's not already started.
  
  @return true if it is successfully started by this call; false if the
  collector is already running or if there is failure in trying to start
  the collector for the first time.