// When
        Cipher encryptCipher = Crypto.getArcfour(key);
        encryptCipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(key, "RC4"));
        byte[] encrypted = encryptCipher.doFinal(plaintext);

        Cipher decryptCipher = Crypto.getArcfour(key);
        decryptCipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(key, "RC4"));

    }

    /**
     * Get an RC4 cipher instance initialized with the specified key.
     * @param key the encryption key
     * @return RC4 cipher in encryption mode
     */
    public static Cipher getArcfour(final byte[] key) {
        try {
            final Cipher c = Cipher.getInstance("RC4");
            c.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(key, "RC4"));
            return c;