private static String urlDecode(final String encoded) {
        try {
            // Regardless of the charset used to transfer the request body,
            // all percent-escaping of non-ascii characters should use UTF-8 code points.
            return URLDecoder.decode(encoded, StandardCharsets.UTF_8.name());
        } catch (UnsupportedEncodingException e) {
            // Unfortunately, there is no URLDecoder.decode() method that takes a Charset, so we have to deal
            // with this exception.
            throw new IllegalStateException("Whoa, JVM doesn't support UTF-8 today.", e);
        }
    }
Percent-decoding method that doesn't throw.

@param encoded percent-encoded data
@return decoded data
container-core/src/main/java/com/yahoo/jdisc/http/server/jetty/FormPostRequestHandler.java