import javax.crypto.*; import java.security.Key; public class AES { public byte[] encryptCtr(Key key, byte[] pt) { try { Cipher c; c = Cipher.getInstance("AES/CTR/NoPadding"); c.init(Cipher.ENCRYPT_MODE, key); return c.doFinal(pt); } catch (Exception e) { throw new RuntimeException(e); } } public byte[] decryptCtr(Key key, byte[] ct) { try { Cipher c; c = Cipher.getInstance("AES/CTR/NoPadding"); c.init(Cipher.DECRYPT_MODE, key); return c.doFinal(ct); } catch (Exception e) { throw new RuntimeException(e); } } }