code: protected void appendProjectionOnFields(SolrQuery solrQuery, List<Field> fields, @Nullable Class<?> domainType) {
  
  		if (CollectionUtils.isEmpty(fields)) {
  			return;
  		}
  		List<String> solrReadableFields = new ArrayList<>();
  		for (Field field : fields) {
  			if (field instanceof CalculatedField) {
  				solrReadableFields.add(createCalculatedFieldFragment((CalculatedField) field, domainType));
  			} else {
  				solrReadableFields.add(getMappedFieldName(field, domainType));
  			}
  		}
  		solrQuery.setParam(CommonParams.FL, StringUtils.join(solrReadableFields, ","));
  	}
docs: Append field list to {@link SolrQuery}
  
  @param solrQuery
  @param fields