code: @Override
      public Map<String, Object> toSource() {
          Map<String, Object> sourceMap = new HashMap<>();
          if (boost != null) {
              addFieldToSource(sourceMap, "boost", boost);
          }
          if (createdBy != null) {
              addFieldToSource(sourceMap, "createdBy", createdBy);
          }
          if (createdTime != null) {
              addFieldToSource(sourceMap, "createdTime", createdTime);
          }
          if (maxSize != null) {
              addFieldToSource(sourceMap, "maxSize", maxSize);
          }
          if (query != null) {
              addFieldToSource(sourceMap, "query", query);
          }
          if (term != null) {
              addFieldToSource(sourceMap, "term", term);
          }
          if (updatedBy != null) {
              addFieldToSource(sourceMap, "updatedBy", updatedBy);
          }
          if (updatedTime != null) {
              addFieldToSource(sourceMap, "updatedTime", updatedTime);
          }
          if (virtualHost != null) {
              addFieldToSource(sourceMap, "virtualHost", virtualHost);
          }
          return sourceMap;
      }
docs: ======