code: public boolean hasContentTypeEngine(String contentTypeOrSuffix) {
          String sanitizedTypes = sanitizeContentTypes(contentTypeOrSuffix);
          String[] types = sanitizedTypes.split(",");
          for (String type : types) {
              if (engines.containsKey(type)) {
                  return true;
              }
          }
  
          return suffixes.containsKey(contentTypeOrSuffix.toLowerCase());
      }
docs: Returns true if there is an engine registered for the content type or content type suffix.
  
  @param contentTypeOrSuffix
  @return true if there is an engine for the content type