Signature sign = Signature.getInstance("SHA512WithRSA");
sign.initSign(kp.getPrivate());
try {
String[] res = fillOutFormDirect("SPKAC=" + URLEncoder.encode(Base64.getEncoder().encodeToString(spk.getEncoded(sign)), "UTF-8"));
Signature sign = Signature.getInstance("SHA512WithRSA");
sign.initSign(kp.getPrivate());
try {
String[] res = fillOutFormDirect("SPKAC=" + URLEncoder.encode(Base64.getEncoder().encodeToString(spk.getEncoded(sign)), "UTF-8"));