code: public static List<HttpCode> getHttpStatusCodes(List<BinaryAnnotation> binaryAnnotations) {
          if (binaryAnnotations == null) {
              return Collections.emptyList();
          }
  
          List<HttpCode> httpCodes = new ArrayList<>();
  
          for (BinaryAnnotation binaryAnnotation: binaryAnnotations) {
              if (Constants.ZIPKIN_BIN_ANNOTATION_HTTP_STATUS_CODE.equals(binaryAnnotation.getKey()) &&
                      binaryAnnotation.getValue() != null) {
  
                  String strHttpCode = binaryAnnotation.getValue();
                  Integer httpCode = toInt(strHttpCode.trim());
  
                  if (httpCode != null) {
                      String description = EnglishReasonPhraseCatalog.INSTANCE.getReason(httpCode, Locale.ENGLISH);
                      httpCodes.add(new HttpCode(httpCode, description));
                  }
              }
  
          }
          return httpCodes;
      }
docs: Method returns list of http status codes.
  
  @param binaryAnnotations zipkin binary annotations
  @return http status codes