@Override
    protected byte[] engineGetEncoded(String format) throws IOException {
        if (format == null || format.equals("ASN.1")) {
            return engineGetEncoded();
        }
        throw new IOException("Unsupported format: " + format);
    }
AlgorithmParameters implementation for elliptic curves.  The only supported encoding format is
ASN.1, as specified in RFC 3279, section 2.3.5.  However, only named curves are supported.
common/src/main/java/org/conscrypt/ECParameters.java