presto-main/src/main/java/io/prestosql/operator/aggregation/AggregationFromAnnotationsParser.java/AggregationFromAnnotationsParser/getNames
class AggregationFromAnnotationsParser:    private static List<String> getNames(@Nullable AnnotatedElement outputFunction, AggregationFunction aggregationAnnotation)
    {
        List<String> defaultNames = ImmutableList.<String>builder().add(aggregationAnnotation.value()).addAll(Arrays.asList(aggregationAnnotation.alias())).build();

        if (outputFunction == null) {
            return defaultNames;
        }

        AggregationFunction annotation = outputFunction.getAnnotation(AggregationFunction.class);
        if (annotation == null) {
            return defaultNames;
        }
        else {
            return ImmutableList.<String>builder().add(annotation.value()).addAll(Arrays.asList(annotation.alias())).build();
        }
    }