docs: protected String getMediaType(
              HttpServletRequest req,
              HttpServletResponse res,
              PipelineEventReader<CharacterEventReader, CharacterEvent> pipelineEventReader) {
          final String mediaType = pipelineEventReader.getOutputProperty(OutputKeys.MEDIA_TYPE);
          if (mediaType != null) {
              return mediaType;
          }
  
          this.logger.warn(
                  "No mediaType was specified in the pipeline output properties, defaulting to "
                          + DEFAULT_MEDIA_TYPE);
          return DEFAULT_MEDIA_TYPE;
      }