@Override
 public String[] getTargetVarNames(AggregatorConfig aggregatorConfig) {
   Config config = (Config) aggregatorConfig;
   String targetName =
       StringUtils.isNotNullAndNotEmpty(config.targetName) ? config.targetName : config.varName;
   int percentage = getEffectivePercentage(config.percentage);
   return createFeatureNames(targetName, "p" + percentage);
 }
 @Override
 public Aggregator createAggregator(VariableContext varCtx, AggregatorConfig aggregatorConfig) {
   Config config = (Config) aggregatorConfig;
   String targetName =
       StringUtils.isNotNullAndNotEmpty(config.targetName) ? config.targetName : config.varName;
   int effectivePercentage = getEffectivePercentage(config.percentage);
   return new AggregatorPercentile(varCtx, config.varName, targetName, effectivePercentage);
 }