*
 * [Punycode](http://ietf.org/rfc/rfc3492.txt) converts a Unicode string to an ASCII string to make
 * international domain names work everywhere. For example, "σ" encodes as "xn--4xa". The encoded
 * string is not human readable, but can be used with classes like [InetAddress] to establish
 * connections.
 *
 * ## Why another URL model?
 *

            if (StringUtil.isNotBlank(suffix)) {
                buf.append(",-").append(encodeToString(suffix));
            }
            return buf.toString();
        }

        /**
         * URL-encodes text for use in text fragment parameters.
         *
         * @param text the text to encode
         * @return the URL-encoded text
         */
        private String encodeToString(final String text) {

    `HeldCertificate` is a TLS certificate and its private key. Generate a certificate with its
    builder then use it to sign another certificate or perform a TLS handshake. The
    `certificatePem()` method encodes the certificate in the familiar PEM format
    (`--- BEGIN CERTIFICATE ---`); the `privateKeyPkcs8Pem()` does likewise for the private key.