private static boolean isGenericDelimiter(int c) {
    return (c == ':')
        || (c == '/')
        || (c == '?')
        || (c == '#')
        || (c == '[')
        || (c == ']')
        || (c == '@');
  }
Percent Encode the provided byte.

@param data to encode
@param bos with the output stream to use.
core/src/main/java/feign/template/UriUtils.java