public MetricInstance withName(String metricName){
  return new MetricInstance(metricName,maker,dependencyMetricNames.toArray(new String[dependencyMetricNames.size()]));
}

public MetricInstance withName ( String metricName ) { return new MetricInstance ( metricName , maker , dependencyMetricNames . toArray ( new String [ dependencyMetricNames . size ( ) ] ) ) ; }
makes a copy of the metric instance with new metric name .
