new SecureRandom().nextBytes(key);
        new SecureRandom().nextBytes(iv);

        // When
        SecretKeySpec keySpec = new SecretKeySpec(key, "AES");
        IvParameterSpec ivSpec = new IvParameterSpec(iv);

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, keySpec, ivSpec);
        byte[] encrypted = cipher.doFinal(plaintext);

        } catch (GeneralSecurityException e) {
            throw new GeneralSecurityException("Checksum failed while decrypting.");
        }
        byte[] ivec = new byte[8];
        IvParameterSpec params = new IvParameterSpec(ivec);

        SecretKeySpec skSpec = new SecretKeySpec(key.getEncoded(), "DES");
        SecretKey sk = skSpec;

        cipher.init(Cipher.DECRYPT_MODE, sk, params);

import java.security.Key;
import java.security.MessageDigest;
import java.util.Arrays;
import java.util.Map;

import javax.crypto.Cipher;
import javax.crypto.Mac;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import javax.security.auth.kerberos.KerberosKey;

/**
 * Utility class for calculating and verifying PAC (Privilege Attribute Certificate) message authentication codes.