if (!normalizedAttribute.equals(key)) {
        updatedParameters.put(key, entry.getValue());
      }
    }
    for (String value : values) {
      updatedParameters.put(
          normalizedAttribute, normalizeParameterValue(normalizedAttribute, value));
    }
    MediaType mediaType = new MediaType(type, subtype, updatedParameters.build());
    // if the attribute isn't charset, we can just inherit the current parsedCharset