code: public java.util.List<MetricDatum> getMetricData() {
          if (metricData == null) {
              metricData = new com.amazonaws.internal.SdkInternalList<MetricDatum>();
          }
          return metricData;
      }
docs: <p>
  The data for the metric. The array can include no more than 20 metrics per call.
  </p>
  
  @return The data for the metric. The array can include no more than 20 metrics per call.