code: public void addAdditionalFields(List<CmsSolrField> additionalFields) {
  
          if (additionalFields != null) {
              for (CmsSolrField solrField : additionalFields) {
                  m_solrFields.put(solrField.getName(), solrField);
              }
          }
      }
docs: Adds the additional fields to the configuration, if they are not null.<p>
  
  @param additionalFields the additional fields to add