private static boolean isSubDelimiter(int c) {
    return (c == '!')
        || (c == '$')
        || (c == '&')
        || (c == '\'')
        || (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