How to change RSAPublicKeySpec to Key for encrypt?

Question

I have RSAPublicKeySpec and I want to encrypt message with this key.
How to change RSAPublicKeySpec to Key for encrypt message?

Answer 1

I try to do this
try {
kf = KeyFactory.getInstance("RSA");
pk = kf.generatePublic(pubCard);
catch (NoSuchAlgorithmException ex4) { System.out.println("1");
catch (InvalidKeySpecException ex4) { System.out.println("2");
try {
Cipher cipher = Cipher.getInstance("RSA");
try {
cipher.init(Cipher.ENCRYPT_MODE, pk);
catch (InvalidKeyException ex2) { System.out.println("a");
try {
ticket = cipher.doFinal(mes.getBytes());
catch (IllegalStateException ex3) {System.out.println("b");
catch (IllegalBlockSizeException ex3) {System.out.println("c");
catch (BadPaddingException ex3) {System.out.println("e");
catch (NoSuchAlgorithmException ex1) {System.out.println("f");
catch (NoSuchPaddingException ex1) {System.out.println("g");
It cougth exception that "NoSuchAlgorithmException"
What wrong with line
Cipher cipher = Cipher.getInstance("RSA");
please tell me